My dog is a 17 week old pit bull. His behavior is like a 99 year old mans with arthritis. He still is eating, has solid poop, has NOT thrown up and is still drinking lots of water. It takes him a very long time to go down a few steps. He is not playful with the other dog, won't jump onto the couch or bed and is hardly moving around. He's been having a lot of accidents in the house the last two days as well. He's very lazy and lethargic. What's wrong?

A l7 week old pup should not be lethargic and this signifies something is really wrong. Take him to the vet for a check up.

Tick

This is a guess but he might have something called hip displashia. ( I might have spelt that wrong) My dog had it. You might want to bring your dog to the vet as soon as possible.

Hip dysplasia and worms/not wanting to eat are totally different things.. that's a disorder of the hip joint.

A trip to the vet's is in order. Why? He may be in pain, or he may have an infection. Dysplasia is painful, but not a suddenly appearing problem... arthritis in the hips is the root of the problem and usually takes much longer to appear. Another hip problem could be a dislocation, or even a fracture. If you notice an almost total refusal to use one rear leg, this may be the problem. A dislocated hip or even a fracture, are not common, but in the right conditions are fairly easy to cause.

Back injury, like a 'slipped disk' causes symptoms quite like this, but that would be rather atypical for a young pit bull, but can't be ruled out at this stage. I can't tell where you live, but this sort of generalized discomfort is also seen with Lyme disease, a tick borne problem. A generalized debilitating and mildly painful condition is a blood condition called Erhichia, or Canine Pancytopenia... another tick disease. Live near the woods? Not absolutely required, but helps.

Well, as I first said, a job for your vet to sort out. Best of Luck and hope this has helped.