What can cause chest pain on the left side id bloodwork and ekg are both normal?

The most common reason for pain in that location is related to the stomach entrance located just behind & to the left the heart. A backwash of stomach acids irritates the site. People often confuse this with heart issues. There is no reason for a 20 yo to have heart issues. Try some antacida or acid blockers for a while & discuss this with your doc.

Chest point tenderness is more likely to be musculoskeletal rather than heart related and the work-up seems to be reassuring in that regard. If symptoms suggest reflux disease and overweight, losing weight should help in all departments.