It was a pleasure meeting you and Jeremiah in Creel last week.
I would go to the nearest city airport that has international flights. They will have an Immigration office there, or at least they should be able to tell you where to go. And they should speak good english there too.
Then you can request an extension of the visa's term at the nearest Immigration office. It is recommended that you request this extension at least 15 days prior to its expiration. You can resquest an additonal 6 months on your FMT this way.
To extend your visa you should have with you:
-Your passport and a photocopy
-The original FMT
-A letter requesting the extension of term.