if "Speak" was used, following Select All, in iOS notes, is that audio stored anywhere on iPhone or in iCloud? iOS 12 Notes App
when using iOS Notes app, i will frequently Select All, then use the Speak contextual menu tab to hear it read back.  Twice, i have had a subsequent action (like tapping spacebar in onscreen keyboard) delete the text.
  If connected to iCloud, is the "history" of the document available on Mac linked to same account, or do revisions reside only on the device where Note was created?  Lacking both Save, and Undo history, makes data in a Notes file ridiculously fragile!
I don’t think there’s a global undo buffer for iOS notes like there is for macOS notes with versions of documents being stored like TextEdit.


There is a “deleted notes” section you can reference from the notes web app, but it’s not like Time Machine for going to an earlier version. 


I think you might need to change how you listen. Is it possible to speak from an insert point and not speak from a selection? That might lessen the chance of losing data you can’t restore.