You should absolutely see a doctor and tell him/her exactly what you wrote here. We can't diagnose online because we aren't doctors, but from what you describe you are definitely suffering from something. It could be several things, but only a face to face doctor can tell you for sure.

Believe me, I wish I had gone to a doctor at your age rather than waiting until I was 35 and in a major crisis. I would have had the possibility of 11 more stable years.

If you do have bipolar, you will lilely need to be on a mood stabilizer. It could take some time to find the right one.

Anyway, welcome to PC and I hope you keep posting with us.