Please pardon my ignorance, but, if my husband and I had protected sex and then fell asleep while he was still inside me (post orgasm - yes he came) and then the condom fell off inside of me while we were asleep, what are the odds of pregnancy?

Tiny backstory: we have a 7 month old, I had an emergency c-section so we’re waiting to have our next one. I’m breastfeeding and my supply was just enough to start with so we opted for condoms as birth control (yes I know it’s not 100% effective, neither is birth control. I got pregnant on the pill ten years ago and pregnant with an IUD last February.) it was around ovulation time, and I had EWCM.