Just like an hour ago, I was at my friend's house messing around until two of my friends noticed a red spot on the side of my head. I looked in the mirror and I was surprised because I don't know how I got it and I don't know what it is. It does not hurt or itch or bother me in any way except that it is very noticeable. Does anyone know what it is? Here is a picture of it. The red spot is a little darker than what the picture shows.

http://img153.imageshack.us/img153/8166/downsized0221092217nv1.jpg