Suggest Treatment For Skin Burn On Leg

I burnt my leg on the exhaust of our motorcycle. Right on my calf just under my knee. It has been 3 days and it seems to be getting worse. the pain is unbearable. the burn is about the size of a baseball. Half of it it blood red where the skin peeled back. it oozes and tries to scab, but when I cover it to keep it protected, a scab wont form. I can hardly walk. the skin around the blistered skin is red like a light sunburn. is this a second or third degree burn? What should I do?