Strange things happening with page count

Hi,
I have a long document (writer 5.2.2.2, x64; win7) which was fine until i changed some of the defined colours (tools>options>color ; changed rgb settings for some colours with modify). After OK the document went 'jittery;' i saved and quit. When i reopened, all my footnotes seem to have been displaced and the page count at bottom left began at around 999 (which i think is too low) and gradually started decreasing; currently at 27 where it seems to have stabilised. Scrolling through the document shows page boundaries seem to have disappeared. Any idea what's going on?
Thanks
Gary