Good. Take a minute to rest. Feel the pain subside. Feeling better?
Then put the clamps back on your nipples. Does it feel more intense putting them on this time? Stroke your pathetic cock again. Fast this time. Stroke yourself to the edge once again.
This time when you reach the edge try and keep yourself there as long as you can without cumming. Concentrate on the edge. Let the pain blend into the urge to cum.