Who can i talk to about bipolar?

For a long time now i've been going through ups and downs that affect my daily life. Some days i dont want to get out of bed, feel insecure, and probably come across very moody. I also start looking at small faults in people and scrutinize them. Then sometimes i feel on top of the world, like i have a great future ahead of me. I feel super confident and social, and want to do things like ring up and meet old friends. It fells like i'm constanly trying to get into that good mood but his often just makes me more unhappy. i want to talk to someone to see if am bipolar but i dont want to speak to my family about it. Is there anywhere i can just drop in to or phone? Thanks.