I feel like I don’t really have Bipolar2.

Is one hypomanic episode really enough to diagnose someone with Bipolar2? I took 20mg of lexapro and after a couple of months i had a hypomanic episode that imo ruined my life, but I feel like I don’t really have bipolar because it was drug induced. I would like to note that I did have some symptoms of bipolar2 before I officially got diagnosed which makes me think I do have it, but I mostly feel like an ‘imposter’.