I'm sorry I haven't heard back from you, with some additional information, but if your cat is in such pain that she's screaming like she's being attacked by another cat, she needs to see a veterinarian in person, immediately.
I see that you wrote quite a few days ago, so things may be different, now. Please let me know if you have brought her to be seen by a veterinarian for a diagnosis and treatment, if needed.
There is a condition called 'feline hyperesthesia' which has some of these symptoms, except for the stomach pain. Here is more information:
If she is still exhibiting the same symptoms, now, definitely bring her to an ER vet center to be seen.
I hope all will be well with your furry girl and please let me know how she's coming along. Also, please let me know the vet's findings. Thank you very much!
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