How to tell if i have bronchitis, flu or pneumonia?

In general: Bronchitis is limited to the lungs and causes coughand typically , no fever. Pneumonia symptoms are similar to bronchitis but are usually a more severe cough , and can include fever, shortness of breath, fatigue, chest pain , and the diagnosis is made by a chest x-ray. Flu is a systemic illness and includes runny nose, cough, high fever, and body aches. It takes an experienced physician to put this togethe.