Feeling kinda crushed and doubting myself; is that normal?

I took the plunge and started formal improv training in early January. Up until last week it's been one of the most fun things I've ever done. I felt exhilarated, creative, connected, and down right giddy with joy.

But last Sunday (6th session) evey single thing I did felt awful; like I could do no right. We were doing scene work that called for each do a short monolog and I threw myself into my character but pathos rather than humor emerged. It felt powerful in the moment but after I could tell our teacher was slightly aghast. All the rest of my work that session was a struggle and seemed to bomb too. I left feeling miserable and doubting I'm cut out for this at all. I didn't feel supported or encouraged either (so much for 'no errors' in improv).

There's an open jam tonight and I'm really having to force myself to go.

I can recall how good things felt before and I don't want to let one bump in the road stop me but is this kinda thing normal? Are there just times when you're going to suck, when it feels like you can do no right? Any advice on how do get yourself back into a good mindset?