Feeling short of breath with little or no exertion isn’t normal. Normal breathing should always return after exercising. Labored breathing can be a warning sign of several medical problems, such as a blood clot in the lung, asthma, chronic obstructive pulmonary disease (COPD), a collapsed lung or lung injury. It may also signal respiratory infections, such as pneumonia, whooping cough and croup, a heart attack or pleural effusion (fluid surrounding and compressing the lungs).
If you are experiencing shortness of breath or labored breathing, consult your doctor.
