iPad home screen icons stuck in top left

Ok so I was playing angry birds then I quit and went to the main part of the home screen. But when I got there all of the preinstalled apps were in the top left. Intrestingly, they all worked fine, but I could position them anywhere (out of the usual restricted grid). The original icons in their original places were there, but I couldn't click on them. Although it is pretty awesome, the main home screen is pretty messy and I would like to know if there is any fix to it, since it isn't going by switching on and off etc.. Thanks for any answers in advance.