Chance of getting pregnant on ovulation day

So my boyfriend knows my cycle like the back of his hand. He knows when I’m safe and when I’m not, and sometimes he even tells me, and then I’m surprised to find out that he’s right when I look on my app. However, two days ago, we had sex. He usually will pull out when he knows I’m not safe. Or he will ask me to confirm with her and see if an hour and then I’ll tell him. But this time, he did not even ask me; he said to me that he was coming inside me, and I told him that I was not safe. I try to move, but he holds onto me. When I checked the app, it was my ovulation day. Part of me is open that fertilization does not occur in another part of me scared. So what are the chances that I could get pregnant from it?