I am feeling so frustrated with my brain tonight!

Every time I work my brain just goes "I'm too dumb for this. I'm not good at this. I can't finish this."

No matter what it is or how much I try to focus it will only let me fixate on my inability.

I just want to get my work done because it's not even hard and I'm working for my mom since COVID wrecked my industry and I want so bad to impress her and prove that hiring me was the right move. 

Does anyone have any tips or strategies for undoing that negative self-talk??  Or even can relate at all? I know I'm not actually dumb but this invasive loop has totally ruined my confidence and in turn, my productivity. 

I just feel so lost and scared for my future.