You should check to see if you have another version of Photoshop open at the same time. With these upgrades Adobe is doing, multiple instances of Photoshop are installed on the same computer. It's driving me nuts trying to figure out which one to use.
Also, you can try pressing Ctrl+Alt+Del on your keyboard and then opening the Task Manager to see if something is screwy with Photoshop. You may want to save the file and then exit Photoshop altogether to start again. Then, open your file and see if the same thing happens.