Well, since your Mom isn't here to tell you...I'll do it for her...here goes.
That's it! You and that little dog are both grounded until that mess is cleaned up and all that laundry is put away!
How did I do?
Actually, my best friend used to do that too...just buy new clothes instead of washing. It was o.k. with me though because we wore the same size and I didn't mind washing them!