Chronic lung conditions such as asthma, COPD, and interstitial lung disease may wax and wane in severity and can worsen quickly and markedly if another problem, such as a lung infection, occurs. Common symptoms of lung disorders include shortness of breath, coughing, noisy breathing, and chest pain. Some people, however, have only mild symptoms or none at all. In these individuals, the disorder may be detected by a physical examination, on a chest x-ray, or by a test to check lung function.