I can completely understand why this is so upsetting. I would be upset, too.

IMHO, I think the only important things that you should focus on right now... is that it was one night, you are okay, and there was no damage done that can't be undone.

I know you feel badly, but try not to dwell too much. Just as you said, it has known side effects. It wasn't your fault. Try to take it in stride, and accept that it was a learning experience.

Not that you need me to state the obvious, but... from now on, maybe be more cautious with your Rx drugs, and consider switching to something that has less severe side effects.