Bloodred dog

I was in creative mode, when i tamed a wolf and i already had 3 dogs tamed. I accidentally hitted this wolf and when my dogs killed him, right in that second i right clicked him and he survived. But he Turned red. Not on the wolf armor, but the whole dog. Then, he turned normal again. I spawned a chicken, hitted it, and my dog turned red again. When the chicken died, the dog was normal again. Then, i took one of my other tamed dogs, hitted him and the red dog attacked him to death.