50 year old male, smoker. No diabetes or high blood pressure, get regular check ups. Today all of a sudden I m having sharp pain in my extreme left chest, which feels like it radiates into my armpit. Certain positions of my arm seem to affect it, though it s not coming from my arm. Seems VERY slightly tender to the touch, but too slight to really be able to say, that s the spot. Deep breaths don t seem to bother it, but exhaling does a bit. could this be a muscle strain? could I have turned the car wheel awkwardly and caused it? Never felt anything in this area before. .hx