What Causes Pain In The Arm, Left Shoulder And Back?

I've had a pain in my left arm, left shoulder and down my back for the past 2 weeks. I get some relief with Advil, but after a day or two it returns. I do alot of crocheting, but I have not crochet in the past 3 weeks due to the pain. I awoke from a sound sleep tonight with a cough (phlemy). Both my parents died of heart disease and heart attack. I've been checked out with a cardiologist yearly and have been proclaimed healthy, however I am on Atenolol 50mg due to palpitations caused from Thyroid disease. Where did this cough come from and should I be concerned with the left arm pain?