Is chest pain always a heart problem?

No. Musculoskeletal pain, acid reflux, anxiety, costochondritis, and lung conditions are common causes. But chest pain with exertion, or with breathlessness, sweating, or radiation to the arm or jaw, should be treated as cardiac until proven otherwise.

Features that point away from cardiac causes: pain reproducible by pressing on the chest wall, sharp and brief stabs, pain changing with position or breathing.

Features that point towards it: pressure or heaviness brought on by exertion and relieved by rest, radiation to jaw or arm, with sweating or breathlessness.