I agree. First, you shoulld check the contract (retainer). Second, if he insists that you should pay the balance and it is not included in the contract, you can file a complaint to the ABA (American Bar Association), just google its website. Before you file the complaint, negotiate with the attorney first. Most attorneys are afraid of complaints to ABA cause ABA will investigate it. If he agrees to withdraw his representation, you should sign a withdrawl contact and get back all your documents.

Good luck.