I as well felt like I was stuck in high school a lot of the time when I lived on campus. I being 20, didn't know what to do or how to act sometimes. I always wondered if some peoples' immaturity is normal for being in college. I finally decided that the immaturity level spreading around really wasn't for me. So i didn't need to pretend it was. Just like I don't think you need to feel like you should be partying all the time... I say, do whatever makes you happy....
But don't grow up too fast.