I bought a black and decker, 2 in 1 steam mop, the one that's raved about on here. If I use it on my kitchen floor which usually has muddy paw prints on it just smears the mud about and doesn't actually clean. Is it only designed for people who don't get dirty floors?! Am I supposed to clean the floor with a normal mop first and then steam mop it??! What am I missing?