Since she came without history, the version that is not a pre-shed: staying grey a long time without ever shedding, patchy discoloured areas especially on the belly which can be scale rot from damp dirty substrate or a burn from a heat source, bubbles or mucus around the mouth or nose, weight coming off, or sheds that keep coming away in pieces.
And do not peel a stuck eye cap yourself. A humid hide or a short shallow lukewarm soak, and if it stays on, that is a vet job.