While I am not familiar with HeadSpace, the Open Graph Meta tags added to your site by Jetpack might cause the changes you saw when sharing one of your posts on Facebook.
To remove these Open Graph Tags, please go to Plugins > Add New > Upload in your dashboard, and install and activate this small plugin:
Once the plugin is activated, Jetpack Open Graph Meta tags will disappear and the descriptions you used in the past should take over.
As per the other warnings mentioned in Facebook Debugger, you'll need to make changes to your theme or use a Facebook Open Graph plugin to add this information to your site. Jetpack doesn't add any fb:admins and fb:app_id tags.