It does not respond to light at all? If not, there might be an underlying eye issue like a detatched retina. Eye issues can also become prominent when there is a kidney or liver disease so please do take this seriously.
I would go ahead and see the vet for an ocular exam to find out exactly what's going on.
Let me know if you still have questions.
The problem with her not eating is that cats can get what's called a fatty liver or hepatic lipidosis when they don't eat. This means that the liver thinks it's starving and it starts to grab fat cells. This ends up killing the liver.
So, you could be seeing the symptoms of a fatty liver, which can come on quickly. If you had the bloodwork before Christmas, you definitely need to return to the vet as soon as you can for repeat geriatric bloodwork.