I signed my paternal rights away. Thinking I was doing the right thing. Now my baby's mother is divorcing the man I gave my rights to, and I would like my rights back.

Are you saying you agreed to allow your child's stepfather to adopt? If so he is the child's legal father now, you are out of the picture. The possibility of reversing the adoption is extremely slim. I would consult a local Family Law attorney to see if there is enough to go to court.