Dark Inner Thighs-Help!

So I have always had dark inner thighs since I was a baby. Here in the past two weeks or less they have gotten extremely dark. This has never happened in all of my 30 plus years. Has this happened to any one, especially women of color? If so, what's your experience with it? I would post a pic but it seems so bad to me. I feel normal it's just unnerving.

Update: I am not pregnant. It also looks like a rash maybe because of how some of the skin is suddenly bumpy.