Help! Should I take plan b? TMI

So I’m new to the pill and I’ve taken it on time, not missed one dose for 2 and a half months now. I usually do the withdrawal method just to be extra safe. I started taking antibiotics (100 mg) one a day for 7 days, which I was supposed to do 2 a day... yesterday me and my partner had sex and, although you’re not ovulating while on birth control, my prediction app says I was two days away from my peak fertile day. I don’t know exactly if he came inside of me a little because I think he didn’t pull out on time. He says he did pull out on time but I saw he struggled and when I touched it felt very wet, but I don’t know. I know that taking antibiotics makes the pill work less or not at all so should I take plan b? Or not worry at all since he pulled out? Can you feel when he cums inside of you?

Thank you ladies 🙏