If it isn't the one you mean and if you created that post using the "Add New" on the main page for wordpress.com here http://wordpress.com/#!/post/ then what you describe can happen and worse still the draft posts may be lost and may not be recoverable.

If you created the post in your dashboard here http://primemont.com/wp-admin/post-new.php/ then you may be able to recover an earlier post revision.

Go to Posts > All Posts, hover over the title of the post, click Edit and check the Post Revisions module for previous saved versions of the post.
http://en.support.wordpress.com/posts/post-revisions/

If you're not seeing the Revisions module while on the editor screen, click Screen Options (top right corner of your Admin page) http://en.support.wordpress.com/screen-options/ to activate it. Then select the post and page modules to include them. http://en.support.wordpress.com/modules/#list-of-modules Then you ought to be able to go here > Dashboard > All Posts > Posts and locate the post and recover it from post revisions.

If you cannot locate the post for locating and restoring a post revision, and it's not in your Trash folder http://en.support.wordpress.com/trash/ then you will not be able to recover it. http://en.support.wordpress.com/trash/#restoring-from-trash