One of my plugins became broke, which unbalanced the server economy entirely. I want to rollback the server before this plugin broke, and now that the plugin is fixed, it would re-balance the server economy. How would I do this?

Load a backup. Most hosts have auto-backups. You may be able to restore one. 

I'm wondering how to do that. I'm hosting the server off of my own PC.

There will be no backups unless you set up automated backups yourself.