There is a possibility of coronary heart disease(CHD) and hence I will suggest you to get an ECG and echocardiography done.Pls consult a physician for that.
Regards and do keep us posted.
You should see a cardiologist to find out how your heart is doing. Having difficulty breathing and walking could be a sign that there is something wrong with your heart valves. Chest pains on the left side are usually angina. Chest pains in the middle of the chest can be plugged arteries or heart attack.