I'm in the same boat. I'm not currently on any medications or therapy or anything, but I think I may have some form of a psych disorder and am afraid to talk to my parents. It makes me sound hypocrytical, but you should really talk to them. They're there to help you. If not them, talk to another trusted adult. A teacher, school councelor, your therapist, a neighbor, a priest/rabbi/etc (if you're religious). These people care about you and are here to help. If you keep these kinds of things all bottled up, it make only turn out to be worse in the end. If you end up being bipolar, it would ultimately be better to start treatment now rather than later. If you ever want to talk, feel free to inbox me or whatever.

Lots of love and best of luck!