There is no real reason you have to stop now, but that being said....all kids go through an easily distractable period and biting and it is usually just a phase.
if you are still uncomfortable, pump just enough to relieve the pressure. Just a little to make you comfortable but don't empty the breast. When you are with him, try cutting out one feeding, then waiting a couple weeks or so till you think you have both adjusted to the new schedule and then try dropping another. When you are at work don't pump if you feel you don't need to, if you do, just do that little bit. It might take a little time for your supply to decrease but if you do it gradually you should not feel pain or engorgement. Whatever you do, don't try to go cold turkey! I can't believe some of the doctors that try to tell you to do that.
It really is awesome you have been able to keep up such a supply with doing primarily pumping for so long! Congrats!