If you have a stomach and headache, feel weak, and have a fever. What is wrong with you?

Viral disease. The symptoms you are describing are most consistent with a viral infection like influenza. Influenza season is now upon us. Please visit a doctor for a diagnosis today. If you are diagnosed early enough, you can receive a medication to improve recovery from the flu. There are other causes for your symptoms, and only a doctor can determine the cause. Good luck.