First, whether she is shedding or not, food should be offered on every feeding day, this includes while she is in shed. If she refuses then she refuses but she should be offered.

Depending on your substrate, the pink belly may also be "pressure" from them laying on their belly on a hard surface. If the rest of the body does not seem dull when the belly is pink, and the pink belly goes away before the eyes get cloudy and if she is active then it is most likely pink due to pressure. If the snake is on paper towel or news paper bedding, you will find this to be the case sometimes. After handling her for ten minutes or so, you will see the belly go back to normal.