My 18 yr old daughter had a kidney infection a couple was ago & recovered with antibiotics. Last night She began throwing up around 3am food, then yellow dry heaves, white, clear, green, now clear regularly every 30 min then every hour even after pepto bismal & liquid nausea medicine. She also had minor diarrhea in between but no longer. No fever but gets very heated before vomiting. Now 1:30p she complains her back hurts around kidney area but only when she moves. Dry heaves are now extended to every hour 1/2 so possibly getting better. She sips ginger ale. We are trying to determine between possible stomach problem/food poisoning or kidney problem & whether to go to the ER. She has no urinary symptoms but starting heart burn. If she continues to extend time between dry heaves, is she getting better probably stomach not kidney?