back again with adobe PS problems..

just a second ago it was fine, but now its.. not. You know when you're using stamp, blur, or brush you can choose to show it in a circle of the size of brush, the paint brush icon, or the target looking thing? Well, I had mine at the size of brush and all of a sudden it became the target. I went to preference, display & cursers, and changed it to size of brush. But it hasn't change and doesn't want to. What's going on here?