A tiny bug is crawling around inside my monitor

Almost certainly a thunderbug (thrips). They're small enough to get through the vents and they're drawn to the light. Whatever you do, don't press on it, you'll squash it inside the panel and then it's a permanent dot. Turn the monitor off and leave it in a dark room for a while, it usually wanders out or dies at the edge where you can't see it. Opening the panel yourself isn't worth it while it's under warranty.