Our 14 year old pit bull has had a tumor on her spine for the past 5 months as shown on an xray. She appears to be close to the end. She is still eating, yet the past 2 days she is shaking. What does that mean? Is it that she is in pain? She was at the vet 2 weeks ago, and he plans to re-evaluate in a week when he returns from vacation. I don't want her to suffer. Any feedback?? Please answer by email to this address. Thanks.