Pull out method done correctly

I’ve seen about a million posts about people getting pregnant while using the pull out method. But to those who did, are you for certain that he pulled out in time?

My dh and I are NTNP and we had sex during my fertile window but got interrupted and he definitely didn’t finish. I just wonder if there’s still a chance of getting pregnant like this.

Quarantine has me bored. 😂

Edited to add: with our other 2 children it took 6 months of tracking to become pregnant.