LOL! Our old cat loved being combed, but matted bits can be a pain. If a cat turns against you then it's going to get bloody. Can be like that when they need to go in the travel box. Not had a cat shit in fear apart from when in said box and that in a car is like being gassed in the trenches.
Now give the cat a pill :)
I think she needs some kind of pill. Apart from the blood pressure ones she's on. I have had similar with the cat carrier. To the extent that we had to buy a dog one that was really big as it became impossible to stuff either of them into the regular cat sized one.
The pill is a really good idea. I'm going to suggest something like that to the vet. Given that they pretty much get the same medication as humans if she didn't take it I will for the next combing session!