Did you even watch this scene? You couldn't be more off if you tried. The reason he ran over Tony's foot is because he put the car in drive prior to Tony knocking on the window. When the car starts rolling, Peeps is already dead. The reason Tony is running with the car is to make sure the hooker is dead. He only shot her in the boob, and he doesn't want to allow her to live because she would snitch/identify him.