Hiya, my cockapoo is 18 months old. She always barks at strangers and used to be growly if we approached her when she was asleep, which is at least a little bit understandable. Today, however, my boys friend was here and my dog was resting on the sofa,she would have seen her coming but when he tried to pet her she bit him. Didn't draw blood but there was a mark left. What do I do?