How come you'e going to uni when you are 17? Just wondering.
As for living in accomodation at 17, it really depends on you as a person. Have you ever lived away before? Have you ever been away from home (on holiday/school trip without parents...) for more than a week? 2 weeks? A month? etc.
Living in uni halls is a BIG change from home. Living without parents is one thing. Having to take care of yourself is another. I think it's great that you want to do it, even if you are conflicted at the moment.
As for making friends etc, there won't be any problems making friends. HOWEVER. As you are under 18, you won't be allowed to buy alcohol or drink it. So this could have an effect on your freshers week. Well, unless you get a fake ID (which I don't reccomend as bouncers see RIGHT through them, no matter how good they are).
You will settle in quickly. Because you are younger than most people, if not everyone, at uni, people will typically take the mick out of you but this will just be banter. Fun and harmless banter. But this is how you build friendships. So if you look at it this way, being younger may be to your adantage lol.
As for homesickness, there's not really much you can do about it. Everyone gets homesick, no matter what age you are. I'm 21. I've been away from home for long periods of time before. I'm used to being away from my parents. I still get homesick. However, there are people that are 18 that have never been away from their parents for more than 3 days and they've yet to get homesick. So it really depends. I've only been homesick once. The longer you are away, the easier it becomes. Honestly. You soon get into the swing of things, get a routine, get a social life, get immersed in your course etc. At the end of the day, if you get homesick, you get homesick. You can ring home, you can skype. If you are that desperately homesick you can go home. I don't really reccomend it as it is good to break through that barrier but if you need it, you can. 4 hours isn't that far. It really isn't .
Good luck