So I'm sitting in class and all of the sudden a super itch hits right next to my lower lip, after class I go into the bathroom and it looks like a mosquito bit me, after a few hours you would hardly notice it was there and the next day its gone. Its cold out still so I don't think there are mosquitos out yet or for that matter any bugs plus I was inside. Any ideas as to what this might be?? This has happened once before except further away from my lip and more on my chin, but its only one bump and then gone the next day.

Sounds to me like an ingrown hair. Like perhaps a small hair got pulled out and was trying to push back through the skin. Or it could have been any other biting insect. They can live in the winter, especially inside where its warm although mosquitoes cannot live like that. They need water to breed and don't have long lifespans. Fleas, mites, and snow fleas all endure the harshest of winters though I've never known them to leave noticeable marks.