Install your prior version from backup ASAP and try again next weekend! Use your paper based process backup to complete your notes until system is up again.
Whenever you perform a major upgrade like this, you need to set a "point of no return", say 8:00pm the night before, for yourself so you can get restore your old version back to where you were by business start on Monday. The time for this depends on how long the restore process takes.
If you don't have a backup available, just use the paper based method and stack them for re-entry until you can get your system back where it was. Hopefully, the installer didn't change your existing S drive database files.
