Someone, anyone... what could be going on in his mind/what is he up to? Help.?

As everyone knows, yesterday was New Year's Eve. My boyfriend of one year went to a big party with some friends. I talked to him last night when he was at the party (he was getting drunk) and I know he was up until at least 4 a.m. The day's almost over and I haven't talked to him once. I know he woke up but we just haven't gotten into contact or anything yet. No emails, no IMs, no phone calls. Nothing. I'm sure he wouldn't mind if I called him and asked how he was feeling because I guarantee he has a killer hangover-- these college boys sure can party-- but I just can't help being kind of worried that he's up to something. Maybe I'm paranoid. I just don't know. It's not an immature thing, it's just a what-do-I-do thing.