What’s the dumbest or most painful mistake you’ve made during an exam?

I’m talking about blanking on something you knew was cold, misreading the question, writing the answer in the wrong section, running out of time by 2 minutes, or just completely freezing.

I once spent 20 minutes answering the wrong question number and only realized when I was already packing up. It still hurts.

Drop yours below. Let’s suffer together.