Correct me if I'm wrong, but when I think of vertigo, I think of that feeling of falling or being pulled down when looking down from heights.
My friend has "vertigo" that is backwards. If he looks up into the sky too quickly at night, he feels like he is going to fall "up" and he gets dizzy and nauseous. Is that normal?! We've been good friends for 7 years so I pick on him about it sometimes, but to be honest I've never heard of that kind of vertigo before. Any thoughts?