I am a 29yo female and I noticed yesterday a sun burned feeling on the back of my upper arm near my armpit but not in my armpit. I have fair skin and therefore I do not sunbathe so I know that isn t what caused it. At first I thought that my shirt had caused some chaffing on my skin. But I changed my shirt and it still got progressively worse. By night time it was getting really uncomfortable and I couldn t bear to have even my clothes graze the area. I decided to put some A&D ointment on it before I went to bed thinking that it would soothe the area. The skin was extremely sensitive to the touch and felt like a severe sunburn. The area is not red whatsoever and I don t notice anything on the outside of the skin. This morning the burning pain is still there. What could this be ?