Congratulations on being accepted to the university of your choice and making it through your first semester! I'm sure it feels great being out on your own, and that you've already made tons of great friends and had many exciting experiences. I'm writing because I want to tell you a few things I wish I'd known when I was in your position as a freshmen; four short years ago. These are things I learned, regrettably late, that make me wish I could redo college. Hopefully, you can learn from my mistakes.
It might seem like getting into the right frat/sorority and hanging out with the "cool people" is a huge deal, but realize that none of this will matter at all in four short years. The people that are concerned with social circles are insecure. They feel a need to validate themselves with an outside authority. Have the confidence to validate yourself and people will love you for it.
At the end of college those circles evaporate and what remains are the lasting friendships you've made. Don't chase coolness at the expense of real relationships. I wasted a couple years being frustrated by my social position when I should have had confidence in myself.