Hi, I am experiencing bumpy rash on my buttocks near the butt crack area. It is very irritating and painful. It is not red, and when I touch it, it appears dry and rough like it would peel off my skin. I have been experiencing it since past few days but it has increased significantly since last 1 week. I had protected sex with a sex worker last week. I think it is a fungal infection, but am worried that it may be an STD. What is your opinion.