He's 2 years old. We've only had him for 4 months. My father in law was about to take him outside, he made a loud sound like he was in pain and tried to bite him. My father in law didn't want to get bit so he backed up. Then dog has been gone all night. So far 11 hours. I drove up and down the neighborhood last night and this morning. No sign of him. What do I do?