I've seen double queens before, never heard of more than that. I would guess you are mistaking large drones as queens? Got any pictures? You have a problem of some kind, after 6 weeks you should have lots of capped brood, larva and eggs. I'm guessing you don't have a queen at all? Do you have some drawn comb for her to lay in, or have they filled it all with honey? I would suggest uploading some pictures if you can get them.
Good Luck