It may not be possible to determine the exact cause without a detailed medical evaluation and
work up. Stomach flu, viral gastroenteritis
, food poisoning, acute appendicitis are few common causes of fever with abdominal pain. In such a situation symptomatic treatment is indicated. Take plenty of water and
fluids. If there is bloating
along with abdominal distension then antacids may be helpful. This is merely an advice and
not a substitute for clinical examination. I hope it helps.