I am terrified i may have contracted herpes from a one nighter. she performed unprotected oral. now i have a sore perineum, very stressed please help?

You did or you didn': The only way to know for sure is to get a blood test in a few weeks for titers (that is medical speak for levels of antibodies in your blood) against Herpes Simplex Virus Type I and HSV II. Get IgM as well as IgG. The IgM are the early antibodies which only stay around for 3 months or so. The IgG are the long lasting antibodies which can last for years. Be more careful in your choices in the futu

Exam: oral herpes is not related to genital herpes. It is certainly time to use condoms. I would advise you to be examined and if blistering occurs, get tested for HSV2. Genital herpes is transmitted through vaginal or anal intercourse, very rare ( not impossible) to be transmitted orally; however, the mouth contain may different bacteria and the perineum is not a very common site- get examined .

Probably not herpes: Initial herpes occurs at the points of direct contact; oral-penlle sex would not infect the perineum. Maybe a slight chance if her mouth directly contacted the painful area, but even with vigorous and prolonged contact, the chance of new herpes from a single oral sex exposure is very low, probably around one in many thousand. But get care if the pain continues or if blisters or sores appear.