BURN mark on my shoulder?

I have what appears to be a burn on my right shoulder right next to my armpit, towards my back. It looks like a burn and its really dry and hasn't been hurting until just now.
It appeared about a week ago, and I definitely have not been burned in that spot! What can it be?BURN mark on my shoulder?
Its an extremely dangerous disease, this disease is air-borne, you see, you or someone put you in an enviroment to where the exceldrian is, exceldrian is little particles in the air that absorb into your skin because of the lack of vitamin d in the sun, it will go away but if it doesnt there is always the fact that love may be distiunguised in the basement or the apartment where there is exceldrian to make your skin even worse.
well leave it alone to make it go away, put sumthing on it to clean. Then use cocoa butter
LOL a stretch mark?
It sounds like a rug burn. Have you been having sex on the floor or something that has a slightly ruff feeling?