couple of articles here , but i would try and get to a vets sooner rather than later if it is causing the dog pain and you concern.
is there another vet in your area you can go to in an emergency or a number you can ring?
in the meantime try and keep the poor thing as rested as possible and try not to allow them to move around too much until you know thw cause of the pain / problem.
how old is the dog, how active, any bumps or tumbles, any previous history?
these are things to consider and advise the vet of.
maybe half an aspirin might help the pain relief.
Neck and Back Pain in Dogs
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