Basically me and this guy were having sex. We are FWB and see each other almost every weekend. We use condoms and I’m 7 months birth control free.

On Saturday morning while we were having sex, he came fast — in the condom and then proceeded to have sex with me with the same condom on until he ejaculated a second time. My thing is...the condom was slipping off a bit during the first time, and when he pulled out the condom came off so fast. Is there a possibility I could have got some of his semen in me? Am I overthinking? Should I get a plan B?