Planted upside down?
You planted it correctly. Those 3 shoots emerged sometime after they cut the plant off, much the same as you would expect regrowth of several buds on a tree branch you cut off. I would leave them and let them grow. However if you want to make more plants at this point you can remove them, allow the wound at their base to "cure" for a couple of weeks and then plant them in a well drained mix to start new plants. That however will leave the old "stump" rather unsightly for a while until new growth appears.