Tired of overthinking

Ok so I’ll start off w i didn’t even have sex it was my first time ever doing anything sexual and i was fingered. I got scared because I’d given him head before and he finished on a blanket and i was scared something may have touched me. I took 2 tests 4 wks later and they were negative and got 3 periods on time. I know I’m not pregnant but i can’t stop overthinking how do you relax I’ve come to the conclusion I’m not ready for sex but i really want to just stop feeling so paranoid i even told my dr abt the situation and she said i was fine. I was scared because at the time i wasn’t on bc but i am now what can i do to calm down and stop thinking about this