Although I have never seen a dog  spin on its butt, I have seen them dragging their butt across a rug. They are actually rubbing their anus to relieving the itching caused by some species of worm. Collect a stool sample and have your vet check for parasites.

Passing blood in urine is not a good sign for animals OR humans, and could be an indication that your dog has a condition that could become life-threatening. A trip to the vet is strongly advised. It might be helpful to have a urine sample with you when you arrive at the vet's office. Good … Read more