Some stop eating when they're blue, some don't. The only way to know is to offer her food the first few times and see what hapens. Once you understand her preference, you can act accordingly; no point offering food to a snake that's refused during the last six sheds.
As for the water dish, she could be trying to assist the shed. Put a humid hide in with her - plastic sandwich tub with a lid, put a hole in the side or lid for her to get in, half fill with a damp substrate like sphagnum moss, vermiculite or paper towel, place it about the middle of the temp range in the tank. If she's having trouble shedding or looking for somewhere damp, that should give her what she needs.
