I would only party on Thursdays or Fridays when you have enough time to make it up over the weekend without upsetting the rest of your life. My sleep gets out of sync too like that, don't know that it has to do with being bipolar (I'm not) but sleep is a "scheduled" thing, circadian rhythm and very touchy for everyone. I don't think you can do things "normal" for a few nights and then be wildly different and not expect to "pay" for it? I'm retired so the worry about the next day is rarely there for me; I went to bed around 9:00-10:00 last night, woke at 1:30 and was awake until 5:30 or 6:00 a.m but had to get up at 9:30 because contractors came to work. But I can take a nap or go to bed early again or whatever I "need" as my body needs it. I think everybody suffers if they mess up their sleep, you sound like other people your age?