Sorry to hear what happened. Try the following and let me know if this works:
Open the document you saved over, then choose File > Revert To > Browse All Versions.
Click tick marks along the timeline to browse versions.
Display the version you want, then do one of the following:
To restore your document to this version, click Restore.
To duplicate this version in a new document, press the Option key and click “Restore a Copy.”
To delete this version, move the pointer to the top of the screen to show the menu bar, then choose File > Revert To > Delete This Version.
If that does not work for you or you do not see the options I explained above let me know.