Hi, thanks for using healthcare magic ,I am sorry that your daughter is unwell
Children can easily before dehydrated if their input is decreased or output is increased (from vomiting
, fever, reduced appetite).
If your daughter is not taking any fluids (in the acute stages we would worry more about her not using any fluids that solid food because as children get better they will eat again) and vomiting then her hydration status needs to be assesssed by her doctor.
Signs and symptoms of dehydration
would be dry skin, skin tenting (when skin is pullled up, it stays up )reduced urine, lack of tears when crying, drowsiness
, increased heart rate
, decreased blood pressure. It is possible that the abnormal sensations in her legs are due to electrolyte loss from the vomiting.
It would be best to take her to her doctor for him or her to take a look at her.
I hope this helps and she feels better soon