8 days ago I had an unprotected encounter in which i was penetrated and there was contact with urine, but there was no ejaculation. The man had not had any other encounters with anyone for the previous few months.
Yesterday after ejaculating, there was a stinging, throbbing feeling for a few minutes that then went away. I ejaculated a few more times to see if it would happen again, but it did not. Instead, I seem to get an occasional painful sensation that is gone as quickly as it comes. It's hard to tell if it's inside or outside the penis, and I do have some chafing on the head that feels like it might be the source of some of it. At any rate, urine is clear, there is no discharge, and nothing seems unusual about my ejaculate.
Is what I'm experiencing a sign of any std?