I have had a rash on my neck, under the skin on my arms, chest and shoulders, it varies in degree, but never goes away. It only itches onmy arms and head. Arms sometimes feel.sunburned. I sometimes sweat like crazy for no reason and having severe headaches. I have a bad fitting crown that causes me to have sores in my mouth. Could this csuse the rash? I have stopped taking anythin, even vitamins, except for xanax to sleep.