Hi. Thanks for your query. Noted the history and understood your concerns. 12 year old daughter not feeling well last week with normal ultrasound for appendicitis and ovaries indicate that there the cause can be flu as you have suspected. You can certainly give her symptomatic treatment for vomiting and dizziness but are also the symptoms that I would advise you to take her to the Pediatrician so that a clinical evaluation, examination and further tests of blood, urine and stool can give the best possible correct diagnosis to get her treated properly. Give your daughter plenty of oral fluids once the vomiting stops and electrolyte solution to maintain water and electrolyte balance. Associated headache may be due to infection or even flu and give paracetamol as per the weight for the headache.