I'm so sorry about your cat
That has to be so scary to watch. It does sound like seizures. You might look into taking her to a neurologist. It may be something that can be controlled with medication.
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~Magnifique Yorkies~
Purchasing from backyard breeders, pet shops, and puppymills perpetuates the suffering of other dogs.
Educate yourself and buy from reputable breeders or rescue.