Pitbull and a Puppy

I have a pitbull named Ares that is now a little over a year old. He used to have a friend named Charlotte (who was a black lab) but our roomates moved out and he was left alone. He got along GREAT with Charlotte and we assumed he would want another friend. I recently got a puppy named Sassy, she’s female and has lab in her.

Last night, I let Ares have a KONG with peanut butter in it and Sassy wanted to play with him and went up to him and Ares bit the puppy! She was bleeding profusly from the nose (which didn’t stop for hours) and Ares was bannished to his kennel for the night. Ares is such a sweet pit, he loves attention and giving it as well, very loving. I’m not even sure if Ares meant to hurt her that much, I beleive he was just trying to tell her to go away. But, I’m starting to see territorial issues here, and I want to stop it immediatley. I also have a cat, and Ares does not seem to mind the cat at all.

In my eyes Ares is an awesome dog, and Sassy is just the sweetest thing ever. I’m not sure what to do about this situation, I want to live peacefully, but I’m scared Ares is going to kill her (and I don’t think it will be on purpose). Please let me know if you have any tips to fix this problem!!