That would seem to be the case indeed.
We're looking into why it reports nearly double of what you actually do use.
Since you would qualify for an upgrade of available diskspace based on your actual usage I have bumped you to the next level, so that may allow you to update the wordpress site. You so have a fairly large backup file as well, within the structure of /wp-content/, I'd suggest downloading that to your local computer for better safekeeping.