What Causes Headaches, Mild Fever And Lack Of Appetite In A Child?

Hello. My 12 (13 on 26) two wks ago started with abdominal pain center upper area. Headache, mild fever and fullness feeling. no eating or drinking. Found bladder infection given bactrum good for about a week. Last wkend it all started up again. Urine showed blood no bacteria. Toook her Cardinal Glennon yesterday in st louis and all labs were norm, ua again showed blood and ketones. They said ketones meant dehydration. They had to stick her 2 and dig to get an iv started gave one bag of fluids. sent her home with ondestrian (nausea) meds. Ive given her zantac max strenth since wed. and tylenol. doc said to not give dairy spicey foods citrus use zantac and no motrin. She is still hurting now it hurts over gall bladder on palpation and headache with mild fever. She also had a sharp pain over the gall bladder area. The hospital did no US or CT.