Medical discharge percentage from the Navy?

I was given a general under honorable conditions discharge back in 2004.I was suppose to get a medical discharge. I hired a lawyer to help me get my medical but I been trying to find out what percentage of my base pay will I get from the Navy? I get 30% right now from the VA which I am also appealing. I've told been told that I should be getting 50% at minimal for my degenerative disk disease. I have other problems too. I just want to know if I can be medically retired instead of given a discharge and at what percentage would I get from the Navy? Can anyone help this vet out?