The presumptive diagnosis in this case would be heart failure.
In the condition of heart attack, the heart fails to pump blood to other parts of the body due to which both the legs and feet swells and also causes dizziness and fatigue. It also leads to shortness of breath. Smoking is very injurious to health. It not only affects the heart but also the liver. Smoking regularly that too for several years will definitely pose threat to our body.