I have episodic numbness, weakness all over, my legs and arms, before a bowel movement which relieves it. I had a lung infection a few months ago.

Merits evaluation. Your symptoms merit a visit to your doctor for a careful history and physical exam as well as routine blood tests and perhaps a 24 hour holter test. Checking your blood pressure sitting and standing, your heart rhythm, and a careful neurologic exam might provide the clues to your problem.