Pulmonary Embolism Support Group
By far the most common form of pulmonary embolism is a thromboembolism, which occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes to the arterial blood supply of one of the lungs. Symptoms may include difficulty breathing, pain during breathing, and more rarely circulatory instability and death.
Keep your head up; it will get better. I started with just easy little walks - not far and on level ground. That helped me to feel less depressed about not being able to be active. I wish I had wore a heart rate monitor when I started my walks, just to track my progress.
Just remember to take it easy on yourself; your body is doing what it is supposed to right now. And healing and repairing takes energy away from all the "normal" things we like to expend energy on.