Is hypomania and depression indicative of bipolar disorder?

Hi there. I currently see a psychiatrist and a psychiatric nurse.You see i have been hospitalised twice with depression butover a month ago i felt high and elated.I wrote down how i had been feeling and showed it to the nurse.She said it sounded alot like i was hypomanic.This isn't the first time i have felt this way.I am 23.My nurse told my pdoc what happened and my pdoc is now considering putting me on a mood stabiliser.I see her on Tues.Is hypomania and depression indicative of bipolar disorder?Thanks