I went to the doc because of depression and it was only because I described how it would go away and I would feel great for a little while that he had me do the questions and then interviewed my wife to determine "great" was very subjective. I get mostly euphoric hypomania and was afraid to say anything because I thought the feelings I had might be related to extensive drug use in my teens and early 20s.

EDIT - symptoms before being diagnosed were similar; cycles of depression and feeling great back as far as early teens, maybe longer. I definitely got depressed back to age 10 for sure (a particular incident from 4th grade sticks out). I did a lot of drugs in my teens and early 20s and much like later (in my 30s when diagnosed) I never said anything about euphoria when I wasn't high thinking it was an after effect of an earlier high.