I think I may have just pulled a crazy old man's testicles.

I was sitting at a bench, when an old man who wasn't wearing pants came up to me, turned around and bent over with his butt right in my face, and his testicles were hanging out of his underpants. His face and testicles looked pretty fake to me, and his legs looked like they belonged to a much younger person, so I assumed I was part of a prank video. I thought it would be funny if I pulled his fake testicles out, so I pulled them. But to my shock, his testicles didn't come out, and the man screamed and then ran away. Nobody came to tell me it was a prank, and I couldn't see anyone filming. How should I deal with my trauma?