Is it normal to be doubting my resolve to make some friends and have a social l

So I'm starting in a new university this autumn and I'm really excited about making new friends and going to the parties and stuff, but at the same time I'm afraid. I'm not afraid of the making friends part, to be honest, although I am a little rusty (not having had friends my age in many, many years).

I have gained confidence and social ability since last year when I went to a different Uni. That didn't really go over well. At the start, some people talked to me and I made their acquiantance but then I stopped going to any extracurricular activities, only talking to them a bit before lectures. Then I stopped going to the lectures, having already decided to study elsewhere, and suddenly I was left with only one person to talk to, and he was REALLY socially awkward. It was so boring, I would have rather been alone.

Still, I think I want some people to hang out with, and that's why I'm going to try harder this time. I'm just constantly doubting myself, afraid that I'll abandon it all again, like I have always done in my life. Avoiding everything, avoiding life. I have always just sat on my computer, wasting my life away. Sometimes I have felt the desire for something more. I'm just so afraid I'll throw my second chance away, too. What should I do?

Note: I'm not going to drink any alcohol, but I will go to bars and try to have fun with drunk people (I laugh easily, my sense of humor is pretty stupid and I like to open up to people even while sober, so I should fit right in, right?)