Hello, Martha and Merry Christmas.
I'm sorry your kitty is having a problem.
If she's not interested in eating, she could be constipated and if she vomited a hairball and is prone to hairballs, some fur, plus hard/dry stools could be causing an intestinal blockage and she could be having a lot of gas, also, which is painful.
It's of great concern, when a cat won't eat, because this can lead to a serious liver condition called hepatic lipidosis or 'fatty liver' within a short period of time.
If you have a Christmas tree up, and decorations, gifts under the tree with ribbon, visitors, etc., it's possible that she ingested something she shouldn't have, like a piece of tinsel, ribbon or someone fed her from the table, etc., upsetting her stomach. In addition, she may have intestinal parasites or an intestinal infection.
It would be advisable to have her seen by a vet in person, as soon as possible, and due to the holiday, if your vet doesn't have emergency hours, you would need to find your nearest ER vet center.
For the moment, continue to keep her away from the chaos of Christmas Eve and monitor her closely; give her some hairball gel like Laxatone or Petromalt and encourage her to drink water.
I hope all will be well with your furry girl!
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