Hello dear, thanks for your question on HCM. You had blunt chest trauma due to accident. But no need to worry at all because your chest x ray is normal. No evidence of any rib fracture, pneumothorax, pulmonary contusions etc, which are common after blunt chest trauma. Your left sided chest pain is mostly due to muscular injury. So better to avoid heavyweight lifting, strenuous exercise. Avoid bad posture and movements in sleep. Start painkiller and muscle relaxant. Apply warm water pad on affected site. Don t worry, you will be alright.