Everyone checks their own face first in a group photo. Nobody’s studying yours as hard as you are.

Everybody in that photograph is doing exactly what you are doing, which is looking at themselves. The scrutiny you are braced for does not exist, because the people you imagine examining you are fully occupied with their own hair and their own eyes being half shut. Attention is scarce, and almost all of everybody’s is spent on themselves.

This is mostly permission. Let the photo stay up, go to the thing in the shirt you are not sure about, put your hand up in class. The audience in your head is watching far more closely than the real one, which has already scrolled on.