For pressure point experts/nervous system experts only!?

He struck probably the "funny bone". Which would account for the numbness and pain you felt after wards. But as for you finding it hard to breath... That's just you either out of shape or not breathing properly during intense exercise. A lot of people literally forget to breath during sparing which can cause you to hyperventilate. I highly doubt your breathing problems were a direct result of being hit in a nerve in the arm.