If I can't shake the mood and do something to change how I'm feeling by more than a tiny fraction.... and it's been around for days.... then I know it's a depression or a hypomania.

If I can move myself forward into another mood (whether it means I've calmed myself down from the hyperactivty, or cheered myself up) then I know it's just a mood and not anything specific.

If it lasts for a short duration and I can clearly see what's caused it - totally just a mood.

If I have the energy and sleep combinations going on, for more than just a few nights, and then I start noticing where my emotions are? Yeah, that's an episode.

But hell, I can be in the middle of a hypomania and STILL have a day where I'm lonely and sad and miserable. But it won't last all that long and I'll be able to distract myself from it easily. Just like when I'm in a depression - I can in fact still go out and have a chance at successfull having a good night - if the depression isn't too severe and I'm not feeling too stressed out about the situation, I might even relax and enjoy myself a bit. Which is great. Problem is, is that if I'm in a depression then as soon as I'm out of that temporary good mood, back comes the crushing sadness. Because that crushing sadness wasn't gone, I just managed to override it for a while. (I realy, really, enjoy those reprieves the odd time I get them!)