Sudden Onset

• If you have the flu, your symptoms usually come on very suddenly. The viral infection starts very abruptly without any warning signs.
  
  

Body Aches

• You will feel achy or somewhat sore all over, but look for soreness in your back, arms and legs. Your entire body will feel sick.
  
  

Dry Cough

• Usually, you will notice a dry, hacking cough. A dry cough is one that does not produce mucus or phlegm.
  
  

Fatigue and Weakness

• If you have the flu, fatigue will basically take over your body, and you will feel so weak that you will not want to get out of bed.
  
  

Stomach Symptoms

• Stomach symptoms, such as vomiting and diarrhea, can occur with the flu. Those symptoms are more common in children than adults.