Sunny is my 10 month old puppy but I'm sure your advice is good for a dog as well as a cat. She is very prone to UTI's due to her inverted vulva so the vet thought that maybe being swollen from heat had caused a UTI OR she thought it could have just been the end of the estrus period with some residual bleeding. We haven't seen a drop of blood since her 2nd dose of Keflex. SO...either the UTI cleared up or her estrus cycle stopped completely. I hate giving her unnecessary antibiotics so I will call and ask if we can stop the Keflex after 5 days rather than finishing the 10 day course. We take her in on the 26th to see if the heat cycle corrected her inverted vulva and then she can be spayed in Feb (fingers crossed!) She sure looks corrected to me but it might be the swelling and the concern is that it will tuck back in. Thanks for your concern and advice!!!!!!!