Blog page broken, page list says (58) but only displays 21

I haven't touched my site for a while (tut tut, I know!) and I just went to write a blog and discovered to my horror that the page was broken.

The other main pages seem to be working, although there are a load of pages (I don't remember writing so many, but I think there are some from my previous site which I've not yet incorporated) which are not showing up in the list of pages, despite the total showing 58. I thought this might be to do with the WPML language plugin, but I've disabled it and it's still not working. Most importantly, there is no page called "blog" (which there definitely was!) either in the core WP list or the Upfront list. I spent a lot of time building that page and my small collection of readers are rather upset!

I have enabled support access so I would appreciate you guys having a look.