+1 for Min and Mark's recommendations. Good luck with the glazing. However, if you find out that the the pots are so over-fired that they will not readily take glaze, then its best to learn from what happened, correct it, and send this load to the shard pile (caveat, if there is something in the load like a piece of sculpture that was extremely complicated/time intensive, it might be worth trying to glaze it).
Sadly, we've all had something like this happen. Trust us when we tell you that It will be a better use of your time and energy to make new pots.