Uh..what would you call this exactly?? :/?!

Uh..what would you call this exactly?? :/?

okay so for a bit of background info : during april i was always sad for no reason. i would want to break down at every little thing (like too much hw/my friend having more enthusiasm towards another one of my friends/stupid thingsl ike that..) and then i started liking this guy who liked me and i was on top of the world. never depressed. then today out of nowhere i got EXTREMELY depressed (like now..) i am 15 and we're having a party today so i should be happy and excited right?? but noo i don't feel like talking to anyone..:[ this isn't bipolar or anything is it?? just a mood swing hopefully? and nothing is bothering me right now. (no school/family troubles or anything..) thank you so much for any help.

Hi.
It is unlikely that you have bi-polar since it manifests generally far later.
It is more likely that your hormones are playing nasty games with you. When i was younger i use to feel like the world was going to end at certain times and at other times feel euphoric. Years later i know when I'm PMTin and that for 2 days i may cry at the most ridiculous thing - but i deal with it fine now because i know what it is. Try keeping a diary to plot mood swings etc... and see if theres a pattern.
The other thing i was thinking was "weather". In the UK we have just come through winter and everything is currently bleak to say the least - Seasonal Affective Disorder - does affect some people and can leave them very blue to say the least.
I still think the diary is the best bet.
Take care and be kind to yourself. x