Why dont the pages load in the WordPress editor?

Hi there,

When I log into wp-admin and click on the Pages tab in the dashboard.. I notice none of my pages will load.
Therefore I am unable to edit any of my pages. I cant edit the home, about, gallery and contact page.
I am able to create a new page and edit that without troubles, but all my existing pages wont load.
There is just a circle loading image displaying all the time.
There weird thing is that when you access my site.. the pages load all the information and load perfectly.
Its just when i log into wp-admin they wont load so I am unable to edit them. Do you have any idea why it is like this?

I am not sure if this is a problem with the theme or wordpress.

Thank you