In a pretty similar position here in that I haven't really clicked with the people I live with. By the time I realised I wasn't going to be good friends with any of them, groups had already formed elsewhere in the halls and the way it's set out makes it pretty hard to meet people other than those near you.
On the other hand, I know there are many people with this problem. You throw a random group of people together and the likelihood of them becoming best friends is definitely not a given. I've met quite a few really nice people on my course and through coursemates and while quite a few of them are mainly close to their flatmates there are several others who, like us, just haven't clicked with them. It will take a bit longer, but you'll find others in the same position as you and it's definitely not too late imo. I'd recommend societies if you haven't joined some already as you're more likely to find others in the same position as you there and even if you don't just mention to people that you've not bonded with the people in your flat. I've gotten a few invitations and phone numbers this way - people are still really open at this point and I reckon they will be for at least another few weeks. Just get out there and talk to people a bit, even if it's just small talk because it provides an opportunity to come back and talk again until you get closer.
I don't think anybody is really close to the people they've only known for 2 weeks, some are just good at faking it, for security, and many just cling onto their flatmates because it's the easiest thing to do when you're somewhere completely alien and things are a bit overwhelming. It takes a while for real friendships to form, I think we just need to adjust our expectations and be patient. Keep talking to the people you're on good terms with and don't give up yet!