Make a stupid mistake, feel bad
I had an assignment due a couple weeks ago in my research class, and it was worth a pretty big chunk of my grade. My prof is a grad student and is very chill about late grades. I had been putting it off for a while because I was really nervous about it, and I waited too long and she ended up putting it in as a zero. It brought me down a whole letter grade, and I feel super silly about being too nervous to turn it in. Whole thing took me like 30 minutes in the end. Lesson learned, 100% my fault, but it sucks!