I was just diagnosed as BP II about 6 months ago. After years of struggling with my moods, I was glad to finally have "a name to go with the face." It took me a while to realize it was actually a problem because my moods are usually mixed and/or rapid cycles. I just thought I was crazy, or had permanent PMS
But now with meds and therapy everything is starting to level out, and its hard for me to think that I was living in a world I didn't have to.
Regarding being diagnosed without being told; I have a similar story. When I was in the military I was sent to a psych because of my eating disorder. After I had one session with this so called doc I was put in for separation.(involuntarily being kicked out) I thought it was for the eating disorder, but later found out that the psych diagnosed me as having Borderline Personality Disorder with suicidal tendencies. I dont know where the heck that came from, and how they can diagnose someone with something like that without telling them. Go figure though, thats just the military.(I'm a little bitter about many things the military, namely the Army, does.)
I think going to see a psych and talking about your current issues and moods might help with the diagnoses. If it turns out you are bipolar, you can get the meds and help you need. Good luck and keep us posted.