Mo, I hate it when I have a wierd mood/feeling and can't figure it out either. Lately I've been trying to just BE in the mood, and feel it and let it pass. Many times there's no reason, and many times the reason will come to me at a later date (sometimes when I get more info that puts the puzzle pieces in place). Sometimes I'm just moody.
I usually feel a little out of sorts until I figure it out though.