Yes, Aspirin is fine for dogs. I would NOT advise giving your puppy ANY pain medication until you have talked to your vet. An overdose of aspirin could be fatal to your puppy. Aspirin, as with ALL pain meds, may not be tolerated, or it can cause an upset stomach or ulcers in dogs.

I hope your pup feels better soon. Your vet will prescribe him a pain medication, until then, restrict your pups activity.