Worried about surgery incision healing

My dog recently had mammery masses removed. Three days after surgery I sent a photo to my vet and they said the incision (at this point) looked fine. She finished her antibiotics two days ago and just today the incision started looking worse. I am taking her first thing in the morning but I am wondering if anyone knows or can offer information.
First photo is the incision two/three days post op I sent to my vet and they said it looked ok.


this is it now