Ok so I watched it and I don't know what you guys are talking about...he isn't horrified at all. He keeps putting his hands up to his head and bending over because he is obviously injured. He keeps checking to see if his head is bleeding. He seems pretty nonchalant about the dog and more worried about himself.

It would be really weird to see that from the woman's perspective. At least she went back and tried to keep the dog from running off.