Hello,
As I was going through your post, the differentials that came to my mind were eczema and contact dermatitis. It
does not look like a fungal infection. If
triamcinolone which is a highly potent steroid is causing you discomfort you can talk to your dermatologist and get yourself prescribed low potency steroid like hydrocortisone. You should also wear cotton undergarments and apply some calamine lotion on the rash.
Hope it helps. Take care and regards.