Trouble with hundreds of backlinks

Hi,

I recently found loads of Not Found errors in Webmaster Tools. When I checked them I saw that Google is picking up url’s for my site https://www.smittenbybritain.com that look like this:

2010/11/crackin-its-bonfire-night/www.smittenbybritain.com

Of course these cause 404 errors.

As you can see, my site url is being attached to the end of the post url. It looks as if I’m backlinking to myself. What would cause this?

Would a plug-in cause this issue?

I’ve been trying to figure this out for the last few days and I’m stumped. Any help appreciated.

Thanks,

Melissa