Sternum hurts right in the middle at the lowest point heart problems ruled out no problems eating swallowing or breathing what could it be?

Chest pain: There are many causes of chest pain which include: angina (cardiac), inflammation of the esophagus, bronchospasm, pneumonia, pleurisy or costochondritis, to name only some. A comprehensive evaluation is needed which can include an ECG, chest xray, bloodwork and a physical exam. Costochondritis usually causes pain worse when applying pressure to the chest. Go to the ER is worse.