Hi,
Yes, that is possible if you did not have these fields protected. This tutorial can help you check that: How to Manage Protected Fields
The box next to the field must be checked for it to be protected.
You can restore from a backup to return your collection to a state before you reset local changes. Once restored, you can protect the fields and then reset local changes again. Here is a tutorial on how to restore from a backup: How to Restore from Backup