How can I tell the difference between a chest infection and a regular cold or flu? 

A chest infection often causes symptoms that are more severe and last longer than a regular cold or flu. While colds and flu usually affect the nose, throat, and sinuses, a chest infection typically involves the lungs and airways, leading to a persistent cough that may produce yellow or green phlegm, chest tightness or pain, shortness of breath, and wheezing. You might also experience a high fever, fatigue, or a feeling of breathlessness that doesn’t improve with rest. These are signs that the infection has moved deeper into the chest, rather than remaining in the upper respiratory tract.