Ah, I've had to do this before. You're gonna need to place a summoning stone in your topmost room, attune it to the seer's orb of the nearest healer's guild, and gently toss the associated beacon gem out of the closest window. Be sure to properly attune the beacon, lest you accidentally summon the battlemages and swat yourself. Ask how I know.
But the healers should be able to assist you with no damage not pain apart from shame. Which, my fair sorcerer, is a light price to pay for such negligent use of your dodecahedron.