Page Heirarchy Not Working

Hi,

Please help! I have been working on my site for a few days and suddenly today my page hierarchy is not working! All my pages are still visible under the pages tab, and I can view each of them in turn, but they are not showing up on my main site on my menu’s.
My site is http://bodytalksystem.co.za/wp/

I have been playing with alternative themes today – I don’t know if this may have caused something to falter?
Thank you
Candice