How Do I Know if I Have the Flu? You may have the flu if you have some or all of these symptoms: Fever* Cough Sore Throat Runny or Stuffy Nose Body Aches Headaches Chills Fatigue Sometimes Diarrhea & Vomiting * Not everyone with the flu will have a fever. Image If you have any questions regarding the flu, please visit the following websites:CDC – Seasonal InfluenzaMassachusetts Department of Public Health – FluCDC – Tips for Preventing the Flu