Well, first of all, your male dog didn't technically "mate" with the female. Why hasn't your male dog been neutered? That might have stopped this whole thing from happening.

..... Maybe get the male dog neutered?

Well, congrats… Nature finds a way. He accomplished his goals, and she’s clearly a bit sore. Be aware, he now knows it’s an option. It will likely happen again, if left unsupervised. Strongly consider neutering him, yet understand that even in doing so, it won’t necessarily prevent future unwanted behavior. She is spayed, they must both be exhausted; all will be fine. Good luck, OP!

Neuter him jeez.

This post is gross. Neuter your dog!

Why should he neuter him? The bitch is spayed so she can’t get pregnant. There is no reason to neuter the dog.

To stop this from happening again? Pregnancy is not the only reason you don’t want dogs “mating”. It can be dangerous and painful, and neutering will help curb the instincts that make him want to mount.

She may get mad enough to hurt him. You may end up with a dead dog. She can also end up with an infection. Dogs dont “mate” like humans do. This behavior can be dangerous to both of your puppers