Suggest Treatment For Sternum Pain

Lately I have been having this dull pain in my sternum associated with cold toes (even when I in entirety am hot), that has graduated to a dull burning in my calf muscles as well as a sharp stab-like pain above my right breast, and a pressure in my right ear. I am quite overweight (currently 5'4" and 210lbs - I had recently gained 35 lbs due to lack of exercise and emotional stress), but I went to a doctor and found I do not have Diabetes, High Cholesterol, or even High Blood pressure. When I tried to explain this to said doctor he didn't listen, so I am still very worried. The pain is only getting worse with time and I find that now when I try to exercise (even if it is a very minimal effort) my heart pumps very heavily and very forcefully. Can anybody help me decide what to do?