Hi,
When a cat doesn't eat for a period of time, such as you describe, they are at risk to develop hepatic lipidosis (fatty liver disease), and this needs to be treated by a vet right away. This is probably what's happening and is why you saw yellow streaks in the liquid that she vomited. She has nothing in her stomach, so she's vomiting bile and acid. When the stomach is empty, it produces acid, which in turn causes nausea, and that's probably why she vomited at the mere smell of the food.
Your cat should be brought back to the vet to assess this situation, and she may need nutrition IV. It's very good that she's been drinking, as that will help clear up the UTI, but the antibiotics could be irritating her system as well, and may need to be changed.
Also, and most importantly, if you feel she might have ingested some of this liquid laundry detergent, she should be treated for possible poisoning, as well. Do you have a vet ER nearby? If not, look in your Yellow Pages under Veterinarians and find a local listing that shows emergency hours/emergency phone number. I feel it's extremely important that she be seen today!
Please keep me posted on her condition and what the vet tells you.
Cher
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