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Crying while walking could be caused by a variety of conditions. Have you noticed if he is urinating and defecating as usual? If he has not been urinating, he may have a urethral obstruction, which is an emergency situation in male cats. It may hurt his bladder, when he walks, if it is full and he can't empty it himself, due to a blockage.
It's also possible that he has a stomachache or could be constipated and that is causing pain. If you have seen him both urinate and defecate within the past 12-24 hours, there shouldn't be anything to worry about in that arena.
He could have jumped down from a height, landed awkwardly, and caused injury to his hip, leg or paw. He could have gotten his foot caught in something and hurt it, struggling to get it out.
As you can see, there are many possibilities, so it would be advisable to have Spaz evaluated in person by a vet, as soon as possible, and if your vet doesn't have emergency hours, you can bring him to an ER vet in your area. If you don't know where the nearest ER vet center is located, the site below will help you:
I hope all will be well with your Spaz and please let me know how he's doing and what the vet's findings are. Thanks!
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