What can cause: numb and tingling extremities + feeling like a lump in your throat + tingling in the head?

Anxiety. These symptoms are characteristic of an acute anxiety reaction or hyperventilation syndrome. The symptoms are caused by blowing off too much carbon dioxide and can be reversed by rebreathing the exhaled air from a paper bag which replenishes some of the carbon dioxide. If you're experiencing these reactions often, stress management therapy would be helpful.