Is Durham truly for me?

I've only been able to visit Durham once, and it wasn't on an open/taster day. Academically it really appealed to me (and this is obviously the most important thing), and the facilities seem excellent but my reservations/preferences make me question whether I should be scouring Clearing for the purposes of finding a different uni for this reason, among others (such as missing my offer).

Whilst I'm eager to meet people, join societies and develop new friendships (like any other first year student), I'm quite an introvert, not too socially experienced (something I'd like to changebut it won't be good for me if I'm thrown too far out of my comfort zone too quickly), and like my own space to retreat to when I'm feeling drained. The college system thus intimidates me in a way that the standard university halls don't - how much involvement am I expected to have? What kind of commitments exist? How tight-knit is it (the system in general)? I chose Collingwood because it seems to have the most relaxed vibe, and also seems to be the largest, so increasing the liklihood of meeting people that I'll click with, hopefully.

The other thing is location and the factors that come with it. Obviously it's quite a small town when I much prefer large metripolitan cities i.e. London. If uni is getting extremely stressful/I'm feeling down I'll feel like there'll be nowhere to 'escape to', in a sense. Will I struggle to adjust to this? I currently live in a city and when I was initially thinking about applying to universities months ago, I remember thinking how wonderful it would be to live in London during my uni years and to fill my calendar with exciting day events such as guest lectures, festivals, exhibitions, etc related to my degree or not that often take place in London. Of course I'll lose this opportunity if I go to Durham, but nowhere in London appeals to me as much as Durham's course does.