I recognize that you are shocked and dismayed about what you did but to receive help you will need to be more specific about exactly what folder you renamed. Perhaps, it might be helpful to say why you renamed the folder (what were you trying to accomplish?).
Please don't do any further renaming or deleting until you have heard back from one of the experts here.
@cconrad1234: As DWL says, you'd have to start by saying what "folder" you're even talking about. Your Zotero data directory in your filesystem? A collection within Zotero? What exactly do you mean by "everything is gone"? What exactly are you seeing on screen?
Upgrade Storage
Please don't do any further renaming or deleting until you have heard back from one of the experts here.