Pregnancy chances?

So I was fooling around with my so and he tried to put it in while I was laying on my side( Haven’t had sex yet) that usually gets him off but today it hurt so we couldn’t. So he jerked himself off and was good. We were talking and I said I wanted to sit on his dick. So we tried to do that even tho it still couldn’t go all the way in, he said his tip was somewhat in. He didn’t come from that. I know it’s stupid but What are the chances of pregnancy from that?