I know i shouldn't think this much about it until I know for sure, especially as I don't know if it runs in my family. Actually I don't think so, I guess i would have noticed...
I've already tried keeping a journal, but i never to do so for more than a few weeks. Anyway with my school counsellor we really tried to find a pattern, but nothing really showed up apart the time spans between two mood swings which are always the similar.

Right now I'd only like to know what's wrong and treat it asap... My riding instructor made some fun of me today, I knew he didn't mean it but it was still painful....