Is it feeling like this on the skin, or deeper inside?
Either way, without sores or anything on the skin, I doubt it's herpes. I do think you need to see a doctor. Depending on where you feel the pain, it could be a urinary tract infection, a hernia, or a number of other things that are unrelated to your encounter.
While you're there, you can get tested for STDs, including herpes - ask for a type specific IgG blood test. It takes about 4 months to be conclusive, but the average time to test positive is 6 weeks. I doubt it's herpes, sincerely, but definitely get it checked. Let us know what happens.