If you hadn't found the same problem with Excel, I would have wondered if you had left your database open on your computer since Oct 29 and had some settings set up so that it wasn't saving to disk, but keeping all the data in RAM. A crash that could then leave you with out any saved changes to the file since the 29th. But if your Excel file also lost all data since the same Oct 29th date, this would seem to indicate something else has happened and I'm not sure what.
Some folks get convinced their data dissappeared when it turned out they had more than one copy of their file and they accidentally opened a different, older copy and then saw all their most recent data missing, but it seems unlikely that this would happen with two different applications in the same way.
In general, FileMaker can't on it's own, just revert back to an earlier copy. Every change you make to the file's data or design is automatically saved so this leaves a puzzle as to how your entries disappeared, not only from your current copy, but also all your back ups. An improperly designed cascading delete could delete large numbers of records, but then your backup copies would have the data.