I try to do lots of things outside of school, because I always do really poorly if I'm not balanced. The only thing is that if you go out and get really involved with fun non-school things, you need to develop really, really efficient study habits (i.e. put a LOT of solid effort into an hour of studying.)
But you can absolutely pull it off!! The people who stay in their apts all the time don't necessarily do better. I joined a big chorus here in Buffalo and they rehearse for 3 hours every Wednesday, my boyfriend and I go to museums, the zoo, out to dinner a lot more than we should ($$$), plays, and out with friends.
For me, the big trick has been to think ahead of when you're study which topic, so you're not just winging it. Other than that, I've actually felt more relaxed than I thought I would and am having lots of fun. I guess we'll see what happens second year 😉