Can my neutered rabbit inpregnate my doe?

My buck rabbit was neutered 10 days ago and came out very well from the op. I also have a doe and have no intention on breeding them(that is why I neutered him). I started to let them play nearby, but separetly so they will start getting to be familiar with each other. I built a barrier with stainless steel cubes to cover a doorway. Yesterday the neutered buck managed to get to where the doe was by squeezing himself through I tiny hole! I found them laying next to each other, nobody was humping anybody when I saw them, they could have been together for 5 minutes though, mean while I surprised them and separated them. Is it posible she could be pregnant? would the male be displaying certain behaviour if they had mated (like falling asleep or something)? Thanks for the answeres.