Hi thanks for contacting HCM.... You have complaint of chronic chest pain which has increased in last few days ... Smoking can lead lung elastic tissue damage ... So respiratory examination and auscultation has to be done .... If needed chest x ray and spirometry done for it .... If your pain constricting and feel very severe also investigate with EKG and blood pressure measurement .... According to cause treatment guided .... If no specific cause found by above investigation than it might be musculoskeletal pain ..... For which ibuprofen or other simple analgesic will be useful ... Take care . Advise : pulmonologist consultation....