BF partying

I think there isn't so much a problem in this itself as a problem beyond it that this is a symptom of.

Coming in at 7am from a party can cause practical problems, especially if it happens frequently, but probably won't very often if you're of college age. Beyond that there isn't really much of problem with what he's doing then given the relatively small number of responsibilities people often have at your age (possibly that doesn't actually apply to the two of you for reasons you don't state and you actually do have some heavy responsibilities this impacts upon).

His reaction to your occasional partying is a much more serious issue. It's a major warning sign if someone has issues with their partner occassionally socialising. Someone having issues with their partner being in mixed-sex company goes well beyond warning sign territory and the burden-of-proof is on the other side so to speak - it's no longer a matter of "is there any other evidence that there are issues here" but rather "is there any evidence that this guy isn't just a total lost cause".

The combination of the two though is what really points to things being seriously screwed up. I would have extreme concerns about his whole concept of what your being a couple means.

On your part though, I would have some concerns about why you say "we're supposed to be a serious couple". There's something in that expression that strikes me as odd. Not that I don't think you shouldn't be a serious couple, but just why is that the adjective that came to your mind when you were describing where you feel you should be. At your ages you should hopefully be a fun couple most of the time and not need to be serious all that often. I know that's not what you mean, but there's often something worth considering in terms of which words come to you first.

In both your cases, I think it might be worth examining just what this relationship is meant to do for each of you.