A little fustrated lately..

As someone who has been through pretty much everything you've described here, let me say that you're fears/worries are normal and justified, though I think you may be worrying a little too much. University is a major life change so you have every right to worry. From personal experience, I can say that the person I was in high school and am now, after switching majors (and universities) are almost completely different people.

I will now answer and disprove all of your questions.

-If you have free time, I would spend it researching everything you can about your university, student life, events etc. Find out what clubs there are, how to get involved, the student organization for your program/faculty, frosh week events, residence events (if you're living there), etc. Pack up, organize things if you're moving into residence. Check what courses you're taking now and in the future, minors, look up textbooks (if you can), review high school notes that are relevant to your courses, etc etc. My point is, do something! The first few weeks will be a blur and then you'll be in midterms and you'll be wondering where all your time went to figure out what things you wanted to.
If you're living in residence, again research. If you have a roommate, see if you can contact them. That's what I did and we got to know each other before moving in and divided up stuff to share (kettle, fan, Xbox, etc).
See and hang out with your high school friends as often and as much as you can before university. You will make new friends and you will not see your old ones as much, if at all. Especially if they go to another university. Unfortunate, but true.

-EVERYONE (or normal people) worry if their major is right for them. In my first major, I had people worrying over whether Health Sciences, Kinesiology, Bio-Med, Biology or Chemistry would be the best major for them to get into Medical school, and they were in their first week of class. Nonsense. You will not know if your major is right for you until you're in the thick of it. That's basically what happened to me, but that's a story for another time.
If telling people what your major is annoys you, then just tell them that it's Physics with an Engineering minor or just say it's physics. They probably won't know the difference. My current major did not exist 10 years ago, so I constantly have to explain it to people who don't know what it is.
I don't know anyone who knows exactly they want to do with their life, and if they say they do, they're probably lying or deluding themselves. A lot of people go with the flow and it works for them. I'm not saying don't have any clue, but you don't need your life planned out. You're young.
A lot of people (if not everyone) wants a job they enjoy... their dream job.
As someone who has been through pretty much everything you've described here, let me say that you're fears/worries are normal and justified, though I think you may be worrying a little too much. University is a major life change so you have every right to worry. From personal experience, I can say that the person I was in high school and am now, after switching majors (and universities) are almost completely different people.

I will now answer and disprove all of your questions.

-If you have free time, I would spend it researching everything you can about your university, student life, events etc. Find out what clubs there are, how to get involved, the student organization for your program/faculty, frosh week events, residence events (if you're living there), etc. Pack up, organize things if you're moving into residence. Check what courses you're taking now and in the future, minors, look up textbooks (if you can), review high school notes that are relevant to your courses, etc etc. My point is, do something! The first few weeks will be a blur and then you'll be in midterms and you'll be wondering where all your time went to figure out what things you wanted to.
If you're living in residence, again research. If you have a roommate, see if you can contact them. That's what I did and we got to know each other before moving in and divided up stuff to share (kettle, fan, Xbox, etc).
See and hang out with your high school friends as often and as much as you can before university. You will make new friends and you will not see your old ones as much, if at all. Especially if they go to another university. Unfortunate, but true.

-EVERYONE (or normal people) worry if their major is right for them. In my first major, I had people worrying over whether Health Sciences, Kinesiology, Bio-Med, Biology or Chemistry would be the best major for them to get into Medical school, and they were in their first week of class. Nonsense. You will not know if your major is right for you until you're in the thick of it. That's basically what happened to me, but that's a story for another time.
If telling people what your major is annoys you, then just tell them that it's Physics with an Engineering minor or just say it's physics. They probably won't know the difference. My current major did not exist 10 years ago, so I constantly have to explain it to people who don't know what it is.
I don't know anyone who knows exactly they want to do with their life, and if they say they do, they're probably lying or deluding themselves. A lot of people go with the flow and it works for them. I'm not saying don't have any clue, but you don't need your life planned out. You're young.
A lot of people (if not everyone) wants a job they enjoy... their dream job.
Again with the generalizing, but I know a lot of people my age and yours who want to change the world in someway. I think that as you get older your priorities will change. Wanting to change the world is a noble and important goal, but some people may be just as happy raising a family or having grandkids.

-The university thing also goes with the major thing. You won't know until you're living there. You can do a lot by visiting and taking tours but you won't truly know until you're in the middle of it. University sports aren't as big of a deal up here in the Great White North as they are in the USA, but lots of people go to games and build school spirit and don't like sports. I never (and still haven't) gone to a sports game and have met lots of people. I should go to one at some point. It's a new experience, and uni is full of them.
If you don't want to drink or smoke, don't. I don't smoke and I didn't drink, even in residence until I turned 19 (legal here). Never impacted me in anyway, asides from not being drunk I guess.

I can't relate to your parents all that much, but you find yourself given a monumental amount of freedom once you're on your own. Your life and your own success are up to you. Some people love it and don't know how they survived with their parents and others can't cope. I've found that engineers and science-y types (myself included) tend to be more introverted and quiet than their peers. Not everyone, just my observation.
It sounds like you're a bit more introverted and are holding being more extroverted/outgoing as some ideal you need to achieve to become successful/important/whatever, and it's causing you stress. I know lots of outgoing people who are nice and/or smart and just as many outgoing people who are jerks/dumb. It doesn't make you a better person, it's just a trait. I consider being caring, intelligent and a good outlook on life more important than being outgoing or the life of the party. Some of the most intelligent, successful and funny people are introverted.... look it up. You choose your friends in life so choose those who are outgoing if that's what you want.
Kudos to wanting to become a better person though.
If you'll indulge my armchair psychology a little bit more, you may also be an extrovert who thrives on being with others, but doesn't cope so well on their own. I'm no psychologist.

That "we are all dying, one day at a time" thing is utter BS. There's no biological clock or ticking time-bomb that says exactly how long we have to live. It's influenced by our choices and genetics. Celebrate the life you have because you are here, in the present, not because you're going to die sometime in the future. Wanting to live life to it's fullest is an admirable goal but not if it itself is causing you stress and anxiety.

My (very long) two cents.

haha thanks for the very detailed reply! It makes me feel better. As for the "we are all dying" part, I meant it to be a positive saying in that we get into this daily and dull routine, and that we should be trying new and different things to help give life some variety and experience. But I see what you mean, though.

The university experience has changed me. (I'm going to complete my fourth year this year.) The fact that I was a wallflower in high school and college is completely gone. (Most people say that they don't believe me when I say I was the ultimate wallflower in high school.) It will change you too, and challenge some of your current ideas.

- Current Major Woes --> I think everyone has this worry. I myself didn't like my major until I was in 3rd year. (Probably because I get annoyed with the fact that I'm not the sporty type and my major is full of bloody jocks who think they are better than everyone because they can hit a birdie.) I'm a rec and leisure kid, and my program is filled with random party people who think this is a "bird" major. I myself had to assauge many first years who think their majors are not for them! As for telling them your major, just stick to some humor while explaining it in layman's terms. Develop a stock reply that has a simple explaination and some humor in it. Mine is "I'm a therapeutic recreation major. This means that I create programs that use games/leisure to improve aspects of people's lives, like spiritual, physical, mental, emotional, etc.". It helps to be further in your program so that you have a grasp on what you do in it.

- Right University --> A lot of people choose an university based on several factors that are unrelated to what the university's reputation is. Based on personal experience and a lot of talking to others, I would say...some of the reasons for choosing a school are. 1) It is far enough to discourage visits from the parents, but close enough so that I can deal with the parents if you need to. 2) It's an university that offers my major. 3) Has a reputation for being a party school. 4) It's close to home, so I can live at home without the bills associated with residence.

Also, you won't know that your university is right for you until you are attending. First year is the hardest to adjust to - living on your own is hard, time management is freaking annoying, and finding your niche on campus is difficult. Do some research, find out what are the clubs you are interested in. Frosh week should be a good week to explore some of the clubs, and meet a ton of people. Just be prepared to forget everyone's name until you settle down into a routine.

- Privacy and Parents --> My parents were the same, up until several years ago. You gotta give your parents time and reasons to trust you until they realise you aren't going to go out and get a skinful of alcohol or a snoot full of cocaine. It takes time - I actually got caught by my mother chugging hiding booze from her in high school. Now she knows I'm responsible with booze and my life.

- Extroverts --> As I said, I used to be an extreme introvert. Part of this was cultural - women in my family should be meek and giving. I actually don't like being around large groups - it pisses me off and makes me waste tons of energy psyching myself up for spending time with them. I have times when I just want to spend time alone, and times when I want to be with people. I've trained myself to have fun and not worry about "what would your neighbour's think?" or "what would your neighbour's say?". I'm not an extrovert because means attention, it's because an extrovert is what is needed/expected in this day and age.

I appreciate your thoughts! I agree with your very last sentence-- communication is a very important part of careers and whatnot, but I also enjoy being an extrovert because I simply feel like I experience more than if I live an introverted life. However, I do have my many moments when I'm completely fine being alone, such as for studying. I'm probably more of someone who is in-between an introvert and extrovert, it just depends what's going on at that time I suppose.

And that's a cool major, by the way!

Thank you! I'm lucky that I got years of college experience before university experience. (Two different things, I guess.)
I'm mostly an introvert. Chalk it up to being bullied or feeling different to most people. (If the Internet was big when I was growing up - hoo!) Mostly I like to stay at home and explore things on my own. (I even explored my little ass university town on my own - scary stuff!)