Am I overthinking everything?

Right so I was at my best friends house and we invited three guys round and one of the guys I have been talking to but he said he doesn’t want a relationship but he finds me attractive and we were on the sofa just listening to music but I was cold so I got a duvet and admittedly we were both teasing each other but then he slipped a finger and I mean I didn’t stop or anything but we were in a room with three other people and idk if I should have stopped not only cause he basically wants to be friends with benefits but also cause they basically all heard and now they are gonna think I’m slaggy even tho this is the first time I’ve ever done anything with a guy

Am I just overthinking everything ?