What is your question? Can you appeal? What do you want to appeal? First you need your documents. I would start by doing a Privacy Act request to your last unit. Be specific.
This advice is generic and not designed to substitute for consulting an attorney. Nothing in this response is designed to establish an attorney-client relationship with the requester.
In order for the Army to lawfully discharge you, they are required to give you written "notice" that (a) they are proposing to discharge you (and the reason(s) why); and (b) the nature of the proposed discharge, e.g., GUOC.
If that did not happen or if it did and you still feel that they were wrong, you need to file a petition to upgrade your discharge with the Army Discharge Review Board.
I would recommend that you at least consult with an attorney experienced in military law related issues - there are a number of ex or retired JAG's in NC - to advise you on how best to handle your matter at the Review Board.