Hello, it's good you already consulted doctor. Any age chest should not be considered lightly. Cardiac condition should be ruled out first. Well ECG and echocardiogram can rule out most of the diseases of heart. A more likely cause of your pain would be something musculoskeletal, such as costochondritis. Musculoskeletal pain can be sharp and stabbing , and can be made worse with pressure (by pushing at the affected spot) or movement. If the pain generally occurs in exactly the same area, costochondritis is even more likely. Costochondritis is the name doctors use to describe inflammation of the joint between your ribs and your sternum. It is common, even in the young, and generally improves with non steroidal anti-inflammatory drugs that you can get over the counter