Poor sick kitty

A few days ago my kitty was throwing up, or at least trying to. She just hid under the couch and wouldn't eat or drink anything. I took her to the vet and ran all sorts of tests. Nothing showed up so the vet gave her anti-nausea medication and sent her home. The next day she wasn't any better. I took her back to the vet, this time for x-rays and more extensive blood-work. Everything came back normal. She got an enema to get rid of backed up poop and had diarrhea for a while. Now poor May-may has a sore butt and stinks like poop. She ate a little bit today and I tried to wash the poop off her. Now she's just taking a nap on a heating pad. I didn't want her to get cold with a wet butt. Poor May-may :(