What Causes Itching And Burning On Upper Arms?

Question : I am having a problem with itching and burning on my upper arms. This has been going on for about a week now. I scratch until I bleed. Sometimes it is more intense than other times. This sounds like it is quite trivial, but it is very uncomfortable. I was thinking could it be scabies?

No rashes. Itching only there and on neck. Seems to happen when I get hot and sweat. From scratching I now have marks, with scabs, that bleed when I start scratching more. It only seems to come on when I get overheated and sweat. Like right now I am fine. When I am moving, like cleaning the house and I begin sweating and feel hot, I start to itch. To me this is kind of crazy, but the itching is very annoying. Maybe dry skin. When I do go to my family physician I am going to ask to have my thyroid tested. I am pretty much over menopause, but sweat profusely from my head that it drips in my ears and eyes. When I walk for exercise this is where I sweat the most. Doesn't feel like hot flashes. I have always been a colder person.