My son is 12 years old. He was complaining pain in stomach yesterday evening. we offered lemon water and apple in the evening. He also had low grade fever is between 100 C to 101 C. During night he had vomit 3 times. Early morning onward there is no vomit for last 6-7 hours. Temp is below 100 C. But he still complains stomach pain in the center of stomach. what medicines can be given?