Our cairne terrier is 6. For the past couple of months, he has had trouble walking and seems dizzy. It is mostly in his hind quarters. I lost my job and don't have the money for extensive tests. The vet has seen him twice and we tried ear infection meds but those didn't work. He doesn't seem in pain and seems happy but he can't maneuver. Any ideas or anything I can have a vet test that won't cost a fortune?