What causes chest pain if chest x-ray is clear could it still be the lungs?

Too many to list: Chest has many organs that can cause chest pain - lungs, heart, pleural and pericardial lining, esophagus, great vessels, nerves, bones, muscles to name a few that are all potential culprits of chest pain. People with anxiety and panic attack can also experience chest pain. That's why evaluation by physician with detailed history and physical is critical in order to try to elucidate the etiology.

Anything: Could be a problem with skin, nerves, muscle, shoulder, lung, heart, or stomach. See your doctor for a more thorough history, physical exam and further evaluation.