If he spayed your female cat, she can't get pregnant. If she was already pregnant when he spayed her, he removed her uterus(s) and so there is no pregnancy after a cat is spayed. No matter what he removed all uterus and ovarian tissue.
For some reason, I was under the assumption that they just tied their tubes, although to be honest, I know nothing about that part of the cat anatomy.
Thanks for the reassurance though. I can breathe easy now.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.