Hello, and welcome.
I'm sorry Dumplin is not feeling like herself and has you worried.
From your description of her symptoms, there are various causes, but the main ones that come to mind are an upper respiratory infection (URI), other respiratory-related conditions, or a dental problem like stomatitis or gingivitis. In addition, older cats are more prone to develop hyperthyroidism, which can cause weight loss and an unkempt coat.
If Dumplin has not been eating at all or properly, and this is causing the weight loss, she risks developing a serious liver condition called hepatic lipidosis, so it's important to get her eating again; BUT, if she's not eating as usual, this could be due to oral pain caused by an abscessed tooth or teeth, infected gums, a foreign object stuck in her mouth, or stomatitis. Here is more information about these conditions:
If she feels warmer than usual, she may have fever, so if you have a regular rectal thermometer or a digital one, you can take her temperature to check it. Normal temp. for cats is between 100.5 and 102.5. If she has 103 or over, she has fever and definitely needs to be seen in person by a vet, asap.
If you can get her to an ER vet center, now, that would be advisable. It's important for her to be examined in person so a diagnosis can be made and then she can be treated and feeling much better. If you're not sure of the location of the nearest ER vet center, plug in your zipcode at the site, below:
I hope all will be well with Dumplin and please let me know how she's doing and what the vet tells you, after her exam. Thanks!
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