You still need to keep them separate. Males can remain fertile for up to 6 weeks post neuter. So wait at least another 3 weeks before reintroducing them, though a few weeks more may be needed if he is still too hormonal at that point(honking, circling, and trying to hump her incessantly).
There is also a slight chance that your female could now be pregnant, especially if you heard your male squeak and fall off to the side of her. So you will need to keep an eye on her for any signs of pregnancy, and around 27 days from when they were together, you will want to put a nesting box and large pile of hay in with her just in case she does have babies, which is usually around 28-32 days.
Your other option would be to get her spayed right away.