If you keep pumping your body will keep making it. Your body thinks the baby needs that much milk. I always over produce too. I am almost always tempted to pump but that just makes matters worse. If you don't have to return to work I say stop pumping and let your body regulate on its on. It will suck for a few days and be very painful/uncomfortable but it will pass. If you have to work and will need the stored breast milk keep pumping. 

Just pump and freeze. Your milk production will slow in a week. Your body is still trying to figure out what enough milk is. After my milk came in I was engorged for about 2 weeks before they slowed down a bit. Take advantage of it while it lasts!