Navigation Problems…

Hello. I am having a few problems with navigation on my site, I’ve had it up a while but only just noticed the problem. Once on a page I can’t seem to press the “back” button, also if you click ‘videos’ then click ‘page 2’ the link doesn’t work unless you edit the URL.

Can someone please tell me where I’m going wrong?

Here is the link: http://www.joestaleymedia.co.nr/

Thanks for the support!