Hello,
It looks like chafing skin or eczema. The symptoms are not suggestive of herpes which present as painful blisters. Wash the areas with fresh water. Do not use any cosmetic products at the sites. You can apply some calamine lotion at the rash as it will help in soothing the skin. Also wear cotton undergarments. Application of mild corticosteroid cream and oral antiinflammatories like ibuprofen/acetaminophen are also helpful. If the symptoms are severe then it will be best to consult a dermatologist
I hope it helps. Take care and please do keep us posted on how you are doing.
Thanks for the query.
Looks like you have a drug eruption. Do you take any pain killers regularly or any other medications? You need to stop that. Also abstain from rubbing that area, wear loose underwear. Take care.
Have a nice day