If you have been short of breath and don't smoke?

If it only happened once, then don't worry over it. But if it has been happeneing frequently, it could be adult asthma. Somewhat rare but might be the cause. Certain allergies could also cause shortness of breath. The possibility of heart trouble might also be the cause.

At the end of winter and the beginning of spring, chest infections are quite commonplace. A doctor will diagnose and prescribe and will also rulw out underlying conditions like TB and pneumonia.