Constipation is not a common side effect of the use of Clavamox.
Constipation combined with bacteria/blood in the urine (crystals or UTI?) sounds like something that unpleasant to say the least & most likely a bit painful.
If she is uncomfortable now I would have her in to the ER vet now.
Is she eating/drinking normally today? Is she peeing okay now? Is she trying to poop? Making frequent trups to the litterbox? These are all questions you may be asked at the vets.
Unfortunately our members are not vets and unable to address potentially serious health issues like this one. Time is critical - please contact a vet immediately. Good luck, we'll watch for an update on your pet's condition. In keeping with site policy, this thread will now be closed.
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