My niece is 4 yrs old and has a low grade fever and a headache. She has been to the doctor and is on amoxicillin. She started out with a headache, then a low grade fever that escalated to 105 and vomiting. My concern is she has been on antibiotics for 2 days, she was tested for strep throat and that was negative. What could be causing the headache?
Hi, Does she have abdominal pain or loose stools? Fever, headache and vomiting is most likely from a viral fever. Let her take some rest, take paracetamol 3 times daily even if afebrile(for headache) and Chat Doctor.  This will subside in 3-4 days. Nothing to worry if she is otherwise playful and taking feeds. Get back to doctor if fever does not subside by then, headache is sever or vomiting persists. Hope I have answered your query. Let me know if I can assist you further. Take care