What Causes Small, Red Mark On Leg?

I have this small, red mark on my leg with a small raised off-white dot in the center. I couple more have popped up, but one of them is on my torso. They udes to itch, but now they just hurt. I dont see any puncture marks, but then again, its hard to tell because of the redness. What are they, and how do i treat/get rid of them?