After posting messages on support and looking at themes, my form reverted to an earlier version

1. After editing, saving and trying out live my form, I found that after posting 2 messages on support and exploring themes, when I got back to my form it had reverted to an earlier version. this then autosaved so the live version also reverted. this could be because I used my bForefox back button. Either way how can i avoid this, as I've lost a bit of work (though not catastophic).

2. Is there a way of saving a backup to which one can revert ? (might answer my earlier q about undoing themes)

You can review your recent changes and revert your form back to an older version by the help of the Revision History. If you have any question or issues, please do not hesitate contacting us. We will be glad to assist you.