Hi Dr. Ada. I m 13 years old from New Jersey, and yesterday I broke out in a rash down my neck and the backs of my ears. What is this? I haven t used any new products or cosmetics. I did however go swimming for the first time this year 2 days before the rash occurred. It is bumpy and very red, and only itches when irritated. It is warm to the touch. Could you tell me what this is? Thanks.