I think that the worst thing that my cat Snowball has done is to pee all over my husband's computer while my husband was using it. Snowball was whining and wanting something else to eat besides his cat food. My husband did not give him anything else and Snowball got mad. Man was that a bad day...
My cat brought in a snake one day. It was just hanging from his mouth, all the way to the floor on both sides. He was dragging it around. That was scary enough for me!
Maybe you should call your vet and talked to him about it. It would not hurt to call another vet about it too. You can get more than one opinion. I wished that I had gotten more than one for my pet. My vet gave the wrong diagnosis.