On my blog arrowfansuk.wordpress.com there are posts missing between the post titled “1×18: Salvation Preview” and the one titled “Regulars added for series 2”.
I also have widgets that are meant to be on the sidebar, yet they show up on the footer of the page.
The link would have solved the issue if you had bothered to read it and apply the instructions.
The problem is in this post (as you could have found by clicking on each post title on your main page): http://arrowfansuk.wordpress.com/2013/04/02/regulars-added-for-series-2/
And the problem is an unclosed div tag at the end of the post.
So use suggestion “A” of my post, or edit your post, switch the editor to Text (=code), and Update after removing this from the very end: <div>