Some conditions are peculiar to the genitals, but most genital rashes are simply the many causes of skin
rash anywhere on the
body. The only STD that conceivably could be responsible is
syphilis, but that also seems very unlikely.
If this problem clears up, which I expect it will do, I would just let it go. If it persists, you should seek professional attention, perhaps from a dermatologist. Whatever is going on, you really shouldn't be concerned about HPV, herpes, or any other STD.