Welcome to the forum,
2 days without food can be getting to the point of danger for your cats health, I have 3 that all kinda do the same when petted on the hind corners, they all been fixed by 1 1/2 years,
I hope you can find a Vet on Saturday to check her out for a proper diagnoisis as folks on the forum could only make guesses and you'll want to be sure if something worse is going on,
you could try some of the jell hair ball remover that comes in a tube, it's usually something they like, the dry stuff may not make a difference where the jell could possible lossen a hairball if that's the problem, but that's just one guess of many possibilities,
cats hid illness well and Fluffy may need medical help that's why after 2 days of no eating she may need a Vet to rehydrate her if she's not drinking also,
does she ever go outside?