My guess is the whole thing has started from his not eating. Not eating means not pooping (what doesn't go in, can't come out) Not walking means either: he is weak from lack of food, or he has pain.
Not eating with many dogs can mean not drinking too. Now that's dangerous because they can get dehydrated very quickly. That in itself can cause weakness and can have bad consequences for the whole system and also kidneys.
So -he's not eating because either: he feels pain, or he feels nauseous. Or both.
I think the best thing to do is to get him to the vet as soon as you can. Get him checked out.
Has he eaten anything out of the ordinary recently? Or could he have got hold of anything toxic for dogs (including some human foods like chocolate or onions?)
Has he vomited, and did he have diarrhea before he stopped pooping?
Does he have arthritis? (that pain can put a dog off food)
In addition to the excellent comments made by Ginger, how old is your dog? Did he stop eating first, before he stopped pooping and walking? Have you noticed her breath smelling? Has he been vomiting at all?
If your dog has not eaten or taken water in for more than 2 days, it is now vital he gets to the vet as dehydration will be setting in, which can be fatal. Tony
Ginger and Tony have both made some excellent points. I hope that by this point (I don't know how I missed this post for two days!) you have taken your dog to the vet to have him examined. Do you have an update for us? How is he doing?
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