There are many causes of chest pain. One is angina which results from inadequate oxygen supply to the heart muscle. Angina can be caused by coronary artery disease or spasm of the coronary arteries. Chest pain can also be due to a heart attack (coronary occlusion) and other important diseases such as, for example, dissection of the aorta and a pulmonary embolism. Do not try to ignore chest pain and "work (or play) though it." Chest pain is a warning to seek medical attention.
In medicine, chest pain is a symptom of a number of conditions and is generally considered a medical emergency, unless the patient is a known angina pectoris sufferer and the symptoms are familiar (appearing at exertion and resolving at rest, known as "stable angina"). When the chest pain is not attributed to heart disease, it is termed non-cardiac chest pain.