Rash around the anus?!

Well, it started about 2 weeks ago and for 2 weeks, I let it dry by not doing things that will make me sweat. It first was present just above the anus and now, its on my anus because when I went to use the bathroom, it stung when I tried cleaning up. I checked and the redness spread around the anus as well. So the drying did not help, what else can I do? I've never experienced this before. Thank you.

ps - it does not hurt when I sit or do anything. It ONLY hurts if I touch it for instance, during shower or when I have to clean after excretion.