I've been at Uni for like.. 3 years now (part time) and I haven't made any friends, but I've made tonnes of acquaintances. IMO my Uni is not the best environment to form close friendships in.
Uni has finished for the year now. Over the year, I met lots of people. I had people to sit with and talk to in every class. But I only saw them once a week for a few hours, and there wasn't much time to talk because we were all busy with our work. Our schedules clashed, so we rarely hung out outside of class. At the end of the study period, I never saw any of these people again. The same thing will probably happen again next year.
I think it all depends on the way your degree is set up. Mine involves a lot of individual work, computer-based work, etc. Group-work is minimal. There are no bonding events or anything like that.
One of my best friends from high school is studying Medicine. She has made dozens of friends at Uni, but that's because Medicine is different. They have lots of classes together - and this set-up continues over several years, so there's plenty of time to bond. There's loads of group work involved. There are regular bonding events and parties. Socialising is strongly encouraged.
I have another friend who is super confident, but she hasn't made a single close friend at Uni either. Her situation is similar to mine - her degree just isn't set up for bonding and socialising with other classmates.
What I'm saying is: it might not be your fault. Maybe your classes just aren't set up for that kind of thing. Plus, I think having acquaintances is fine in Uni - you don't really need "close" friends. As long as you can chat a bit and get work done together, that's cool.
If you're looking to form stronger relationships, it might be better to look elsewhere - somewhere where you'll spend time with the same people regularly. A lot of people meet their close friends at work or on a sports team - both of these usually involve seeing the same people several times a week. You'll have more time to get to know other people, and vice versa. I guess regular gaming groups could also work for you if that's what you're into. I don't know much about that, though.
Another tip: try not to push or force friendships. It's better to allow them to form naturally - unless you want to end up 'friends' with people you don't click with at all. I've been through that before and it was truly shit. I prefer having a very small number of great friends over a larger number of people I don't really get along with all that well.