Since last 10 days, i am feeling suffocated and gets normal when take two three deep breaths but again feeling same when lay down straight to sleep. Always have mild pain on left chest like muscular pain includes left side of neck and shoulder. I have odd schedule (as working in IT industry) Sleeping time 3:00 AM to 1:00 PM. Never felt any severe pain except sudden lack of oxygen. No family record of heart/pulmonary disease.