EError establishing a database connection, HELP!

Hi! I am not able to connect to my WP admin panel or page. It is located at http://dovah.desishion.no. I have had some trouble with using Coda today for another page and I accidentally changed something in the config file, however I only uploaded a config-sample file, but instantly removed it from the remote server, and the remote config file is exactly the same as before, when it worked. I have also played around with plugins today, and this crash happened in the middle of a Backup to DropBox backup. Could this have anything to say?

In short: the config file is unchanged from when it previously worked. Is there some way I can change this, by repairing something in phpMyAdmin etc ? I am unexperienced with databases and php… I also know there are hundreds of threads addressing this issue, however I haven’t found one to explain to me my issue.

Looking forward to your help!