I have a 1 year old pomeranian who is unable to walk with his hind legs. He was fine a few days ago running around playing inside the house. Then I started noticing he was limping with his left leg up. He also would stand there staring into blank space with his left leg raised. He can't get up on his own and would need my help. I'm planning to take him to the vet tomorrow. What do you think is wrong with him? Thank you.