HOW AM I NOT PREGNANT?!?

Okay so me and my boyfriend are sexually actively.. I'm surprised I haven't fallen pregnant yet. I need to be a lot smarter and have some kind of birth control but I'm sooooo surprised that I'm not pregnant. He doesn't finish in me he usually pulls out and has to do it with his hand for the smallest time before he starts to cum. I just woke up and I'm like holy crap! How have I not been pregnant yet.. it's also my second to last day ovulating and we had sex last night, no protection or birth control and he pulled out and finished with his hand as I explained earlier.. I'm kinda scared I'll be pregnant after that from maybe like pre cum? Idk but someone help and give me advice! Is his pull out game just strong af? UPDATE: I don't want a baby lol but if it happens then I know we'd be the best parents