Hello Thank you for posting your query in Healthcaremagic. The symptoms you described can be due to lot of reasons related to heart like angina,coronary atherosclerosis and myocardial infarction and lung disorders like Chronic obstructive lung disease,smoke induced asthma etc.To be precise it can mostly be a cardiac cause.But you need to do an electrocardiogram and a chest xray to know the appropriate reason behind your discomfort. I would advise you to quit smoking as soon as possible or it may damage lot of organs in your body.Visit a doctor to rule out any cardiac emergency.Check your blood pressure,lipid profile status,total blood count. Hope this helped.Wish you a smoke free life.