Catseyesbc has your cat been to the vet in the last year for a full blood panel & urinalysis? If not please do so & have your vet include a T4 Thyroid test in the blood panel. A lot of the symptoms you are describing in an older cat can be the same as a cat with untreated HyperThyroidism.
Avoid biting when a simple growl will do
The Spirit Lives As Long As Someone Who Lives Remembers You - Navaho Saying
Vindication ~ For all those pets who became sick or lost their lives from tainted pet food