Do I have no nerves in my foot and is it broken?

D, if you were doing karate your feet and hands would become the same way. You have built up an insensativity to these kind of stress due to constantly using your feet. There is nothing wrong with the nerves in your feet. They are still working as you are able to run and kick and if they were not working neither would your feet. As for your toe it comes from the constant impact from hitting the ball. You may want to consider seeing a podiatrist about having surgery to correct this. The only thing is that as long as you are playing this is going to happen.