pain smile - A smile so fake it could fool a robot, usually when you're h

A smile so fake it could fool a robot, usually when you're hiding the fact that you just got roasted or your life is falling apart.

I failed my math test and smiled like I’d passed with flying colors.

My mom said I was 'disgusting' and I gave her a pain smile that screamed 'I know.'

When my crush asked me out and I said no, I smiled like I was doing them a favor.