Sex day after period ends

So the mans and I had sex on Wednesday night; we started off with no condom for maybe a minute or two, but then he put the condom and came pretty quick after that. My period ended the day before, but I’m still in a wee bit of a panic cuz my ovaries hurt (I’m trying to attribute it to how long it’s been for us, which is almost a month). So my question is, from my described situation, is it possible to get pregnant after your period ends or should I quickly get a plan B? Thank you!