Barbara Winters· Registered
Breast generally become somewhat swollen during estrus because of the hormonal changes and the tissue is likely more fragile. Maybe this could explain the bruising. Also you said the back 4 nipples-might they be traumatized from banging against her legs when walking/running? You might want to check to see if her breasts are warm or hard to the touch, possibly indicating mastitis. A little early for a false pregnancy but as her seasons seem a bit off so might the time frame. Of course I know you'll check with your vet if your concerned.