Breakout of acne/rash on one butt cheek & where the seems of my underwear go on the inside of my thighs right next to my vagina. Should I be worried?

Needs eval. Dear NKhan, is this rash painful, itchy? Does it have blisters? With this location and the fact that it is unilateral, I am concerned about herpes or shingles or a bacterial infection. You need to go to the doctor to be examined. You don't need the ER but should go to clinic tomorrow morning. .