Chances are, if you moved the old queen to the nuc that the original hive will be well underway to making a new queen by now, you would need to check very carefully for signs of queen cells (capped or recently vacated) before you put the old queen back. I would give it another couple of weeks before you put the old queen back. You have a nuc or two, which is what you set out to do, the old hive should be creating a new queen if the old queen was still laying when you removed her and they should be up and running again in a few weeks, if not, then you could combine your nuc back in.