Tried to change URL and it exploded – HELP!!!

I had a wordpress blog that I wanted to make my main site.

Initially it was at: http://www.magnusbogucki.com/blog and then I decided to make it the main page: http://www.magnusbogucki.com

I did this in the admin area where u enter the URL for your blog. I changed it and then got an error – sadly i panicked and I no longer have the error!

However, now if you go to my blog you can see it is very messed up and when I try to enter the admin area it is not even there. Says “broken link”

What do I do??