Changed URL lost everything. HELP!

I built a full site completely outside of WordPress (at http://lifebloodride.org) in hopes that it would be easy to migrate to WordPress, which I’ve never used. Just upload the CSS to the right folder and bingo, right? Wrong. I wanted to use the lifebloodride.org as the main site and use http://lifebloodride.org/blog as the blog.

So as I’m working on the CSS, I decided to change the URL. I got a 404 error and tried to hit the back button. Nothing. All dead ends. Can’t go to /wp-admin, can’t find the themes folder in the FTP, don’t know anything about PHP, and can’t find a single solution online that makes any sense to me.

I’m leaving in 48 hours for a month-long trip and won’t have a computer (I’m building this site to document that trip). Basically I’m desperate.

Can anyone help? If so: many, many thanks!