I LOVE THE NEW SIG!!!

I would be very concerned about her too. I would have thought she would have perked up a little by today. Is she up moving around at all?
Do you know how to check for Dehydration? You get the loose skin on the back of the neck or back and lift up and see how fast it goes back to normal. If it stays loose or doesn't snap back into place quickly then she is starting to dehydrate.
Some kitties get pretty sick with those shots and maybe she is just going to take longer to recover since she was in poor condition.
Don't start balming yourself for that either! You have given her more in the last day or two than she has probably ever had away from you! If there were issues with giving her shots until she was healthier then it was the vets job to determine that.
I wouldn't worry to much about the not eating yet but just watch for dehydration. That is when things get ugly.
How does she respond to you when you come into the room? Is she looking at you? Is she doing anything at all?