Without further information it is very difficult for me to provide the best advice but I shall certainly try.
Please reply when you can and we can continue the conversation.
Sooty is very elderly so we need to be cautious. Given her age, a serious health issue is not unlikely. Her signs are vague and could have many causes including a source of pain (such as dental disease or worsening joint disease), pancreatitis, liver disease, kidney disease etc.
A vet visit is sensible so Sooty can be examined.
They will check her over and may run some tests such as a blood test and abdominal scan.
Treatment will depend on what is going on and may include e.g anti inflammatories s, pain relief and an appetite stimulant.
Offer warm and tempting food such as chicken or white fish and allow her to rest.
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