Page content formatting messed up when refresh, go back in to edit and it goes back to normal but will not save that way???

Hi there!

I've just spent all this time formatting an unlinked page and as soon as I dragged it to the main navigation the formatting completely changed. When I go in to edit the page it snaps back to how I originally had it. Then once I save and refresh, it goes back to the weird format (stacking and shrinking my images) . Would really appreciate any help as I've searched everywhere and can't find anyone with the same problem. Thanks!!