I had a shooting pain in my left breast that caused me to have shortness of breath and i had stabbing pain under my left shoulder blade. help. please.

Don’t ignore this: Left-sided chest pain should never be ignored. While it could be something as simple as indigestion, shingles, or costochondritis, The more dangerous causes of such pain are: Myocardial infarction, angina, pulmonary embolus, pneumonia, or even cancer. A good place to start would be your primary care physician who most likely will order labs, an EKG chest , x-ray, and refer you to a cardiologist.