Isn't it possible you are using versioning without workflow? Because your description fits the behavior when using workflow or versioning with content scheduling. Please see this article on the same topic. I would say that there is currently published some version of the page - so this one is displayed. Then, you create new edited version and set its publishing date into the future. So, this latest editing version is still waiting to be published. And once the date and time will come, the edited version will become the latest published version and it will also change the values in the DB. (FYI, I would recommend getting familiar with the DB structure too).
That being said, if you want to hide the page from the live site, unpublish it then you need to set the Publish To date into past. This way the latest edited version will become the latest published version but based on the date it will be unpublished from live. Then, clear the Publish to field and set new Publish from date, save, done.