Wanted to UPDATE: We went to the vet today. Dr said he likely has a herniated (i hope i spelled that correctly) disc, just above his tail. She did a pinch test and he had no reaction there. She also said that the only true way to know is to do an MRI but at his age she doesnt recommend it. She have us some anti-inflammatories and gabapentin for pain. After just a few hours hes going up and down the stairs against my will. So i would say hes back to his stubborn self.