I'm kimberly I have been smoking for about three years now and for about 4 months now I have been smoking about 10 cigarettes a day instead of my usual 5 due to more stress at work. About 3 weeks ago I started getting discomfort in my left arm as well as a tightening feeling in my left arm. Also I frequently have to burp to be able to breathe normally. I was afraid of heart complication so I visited the er yesterday but they found nothing wrong. This is really scaring me and I really want to know what's wrong with me! Please help with some possible answers.