Thanks to everyone who replied!

I just got home from my first appointment with a therapist today and it went better than I expected. He was very perceptive and picked the right questions to ask. I didn't mention that I thought I might be bipolar till the end of the session (just discussed the main issues I've been having), and he said that he considered it a possibility. I have a follow up appointment and he's going to ask me more questions related to bipolar disorder and talk to me about medication options.

Overall I feel really good about finally getting help.