The hypochondria flared
It has been said that the biggest hurdle for a hypochondriac is knowing that this is the case, but not having a reliable means to distinguish between worry that is part of the condition, and sensations that indicate the presence of disease which is to be acted upon. The two are intertwined; were they not, it would not be hypochondria
Fortunately, she had precisely such a reliable mean. Whenever she was truly sick, it would meow at her and try to give comfort at every turn. Otherwise, it would demand food, regardless of how long it had been since last time, or how much was left in the bowl. As is the case with such things; cats, too, require a means to tell the difference