I made a stupid mistake

Patient: I want to know what the chances are I have a STD and should I get tested? I wanted to experiment with homosexuality and met a guy on Craigslist. He said he was disease free and didn’t have any outward symptoms but I’m worried he lied. It happened yesterday we french kissed and he gave me a hand job but when I ejaculated he put his mouth on my penis for about 20 seconds. I have no symptoms yet.