Problem

Ok i'm having a problem. I just went through a tutorial and everything went fine. Until i tried to add text. I add the text and go to move it over [u know with the move tool] and it switches down to either a layer below it or the background layer itself. I just tried it again and it moved like normal then did the weird switching thing again. What could be causing this? Did i hit a wrong button or something? Thanks for any help. [My program is Photoshop 7]