I recently went for a run and experienced severe chest discomfort for a few minutes. My heart rate continued to increase for an hour or two after that. After doing an ECG (electrocardiogram) and determining that my heart was healthy, the doctor said that it was common for persons my age to have chest pain when exercising. It has been two months and I am not sure whether I am just tensing the left side of my chest or if my heart is having issues. This morning I felt pain in the left side of my chest after drinking coffee. I woke up after receiving little sleep, and ever since then, whenever I yawn or stretch, I experience an unexpected, somewhat intense discomfort in my left chest. However, even though working out is a little more difficult than it used to be, I do not feel like I experience shortness of breath or chest discomfort when working out. The aches tend to arise more while I am sitting, lying down, or drinking coffee. Kindly help.