I didn't consider this side of the problem

One of my fears concerning my depression/bipolar/whatever is going on with me was that if I got really depressed, I'd stop doing school work and practicing my instruments and when I finally got out of it, I'd be in a heap of trouble and need to try to dig myself out of the hole I'd created. What I didn't consider was that I'd become hypomanic and feel so confident in myself that I stopped studying and doing extra credit. Well, that's what happened. I had three tests on one day and I felt so great about myself I just didn't study for any of them. Thankfully, the teachers curved the first tests a lot, but I really never considered that this could be a problem.
-Sam

Lesson learned, right? I've totally done stuff like that too.

What I didn't consider was that I'd become hypomanic and feel so confident in myself that I stopped studying and doing extra credit

I did this in college sometimes -sometimes I was right, sometimes I wasn't. I don't think it was 'hypomania' though, just a skewed view of what I was capable of coupled with, at times, not expecting a test to be so difficult. I say I don't think it was hypomania in my case, because I didn't think I was the smartest person on the face of the earth, or anything so extreme, just that I could get by without studying.

But as someone else said, it's one more lesson learned, right? Gotta study no matter what, and you'll figure out what material you need to work on more than others.