Feed her today. Most geckos are hungry again within a day or two of finishing, and the pale phase you watched is exactly why she went off food in the first place. Shedding costs energy and they are not interested until it is done.
The missing skin is the easy half. She ate it. Almost all of them do, and the usual explanations are recovering the nutrients and not leaving a trail behind. It is not a meal, so it does not change your answer, but it is not a mystery either.