When you click on that red traffic light in your unsaved, document title bar, the document is automatically purged, and there never was any revision history. Time Machine does capture the hidden package folder that may contain this unsaved work-in-progress document, but the Time Machine restore window will not give you access to the package folder contents to check if the document was present during the backup.
If you have not saved changes to a Pages document, and have not clicked the red traffic light on the document title bar, or just quit Pages — then there is a working copy accumulating in your local Library location:
/Users/yourname/Library/Containers/com.apple.iWork.Pages/Data/Library/Autosave Information/Unsaved Pages Document.pages
Note: You will have to right-click on the com.apple.iWork.Pages package folder (it has the yellow Pages icon) in the above path to show package contents from the secondary menu, and proceed further to the document itself.
If you plan on attempting to restore the com.apple.iWork.Pages package folder from Time Machine, make certain that Pages is actually quit beforehand, and that you copy the current package folder to your Desktop for safe-keeping. Restore the specific Pages package folder from Time Machine, and proceed into it per above to see if your document is present. If so, just drag and drop it to your Desktop, and give it a new name (without white-space). If you document is not present, then move just this package folder to the Trash, and put the original package folder back in the same location.
Finally, the first thing that you should do with a new, Pages document is save, and give it a mnemonic name. This will trigger autosave and versioning. As you make changes to the document, they will be autosaved about every 10 - 15 seconds, based on my observations. Versioning will only be useful after your second editing session.