Database Error when trying to access WP dashboard

Hi
I am receiving a Database Error when trying to access my blog. http://servicewithsarah.com/
I wanted to update my theme but first I wanted to backup my data. I downloaded the widget Portable phpMyAdmin and activated it. I have done an export which I thought saved my data.
Now, I can no longer login to the dashboard to makes any changes. It says “Error establishing a database connection”. WordPress is showing I no longer have an account. When you pull up the blog http://servicewithsarah.com/ a blank page is showing. I’m really not sure what to do at this point. I have put in a request with WordPress Support but I have not received a response yet.

Please help!!!

Thanks 🙂