Didn't the vet give you any idea what the bleeding was? It doesn't sound like a heat cycle. Heat cycles last 21 days. I week going in, one week in, and one week going out. You will see swelling of the vulva and blood dripping. Smaller dogs are harder to tell but Presley should be easy to tell. The most critical days are between 9 and 14 on average. But it is better to be safe than sorry and not have exposure at all. Sperm can live up to 48 to 72 hours in the uterus.

Having her spayed would be ok around 6 or 7 months. If she is in heat though you want to wait until about 1 month after the bleeding stops. Having them spayed during the cycle produces more chance for things to happen because of the extra blood flow to that area. Giving it a month after will give everything time to get back to normal.

Basically some vets will do this procedure even if the female is in season. I have heard of things going bad though because of that.