Normally a queen would never put more than 1 egg per cell. But I have read in other forums on the net, that new queens can lay several eggs the first day or two, and the persons having this problem was advised to wait a few days and check again. If there was still several eggs in the cells, you have a laying worker.
Do you know if the swarm queen is the old queen, or if it is an afterswarm with a new one? If it is the old queen, I think she would never lay more than one in each cell.
eivindm