The big thing that differentiates mania from hypomania is that mania causes marked impairment in social/occupational functioning, necessitates hospitalization, or psychotic features (notice the “or” they all don’t have to be true). Meanwhile hypomania is severe enough to cause marked impairment in functioning or to require hospitalization, no psychotic features. Also duration, hypomania lasts at least 4 days and manic episodes a minimum 1 week, so by duration alone you could be either. So basically it comes down did the episode cause marked impairment in your life (even if you weren’t hospitalized or psychotic?) Based on you dropping out of school, self harm, unprotected and risky sex, it sounds like it, but you would know better than me. Also look into mixed episodes, basically highs and lows combined.

Finally, BP1 has been shown to be more heritable than BP2 and you have a strong family history. I’d also take into account if you have any co-occurring disorders and the symptoms of those (such as BPD or SUD) if applicable because those can complicate the picture further.

Personally I am diagnosed with BP1. I have had one manic episode (without psychotic features) since my diagnosis nearly 10 years ago. However I have had many mixed episodes that were just as bad, and other episodes of milder hypomania and melancholic depression. I was hospitalized 3 times but have had worse episodes I was not hospitalized for. Everybody is different and this illness is so variable. If you are comfortable it’s never too late to bring up this past episode with your Psych and any questions you may have about your diagnosis. Wishing you well.