Thank you for the additional information. I am sorry to hear of your dilemma. I realize how frustrating this is for you and I hope to provide you information which is accurate and useful, even though it may not be the news you were hoping to get.
You need to go to the court and check the file for the judgment reported. What I suspect may have happened is that, since the original debt was never released when you paid the $5000, the original lender wrote off the debt and sold it to a debt collection company. That said, if you were never served in the law suit, you can file a motion to vacate the judgment, since, without service of process, the court had no jurisdiction over you to enter the judgment.
While you can do this yourself, it is strongly recommended that you retain local counsel to get this resolved as quickly as possible. There is no reason to learn as you go.
If you need assistance finding local counsel try Martindale Hubble (site rules prohibit us from referring specific attorneys) . Many attorneys themselves use this site to locate attorneys outside their jurisdiction or expertise:
It is a huge worldwide database searchable by location and specialty. The attorneys are all peer rated. So, they represent the top of the profession.