Have been son's Dad since birth signed birth certificate

My son’s mom and I started dating when she was 5 months pregnant. She gave birth to son and i have been only dad in his life. We were not married when she gave birth but married when son was 9months old. Also no one was listed on his birth certificate as father at time of birth. We later decided to list me on the birth certificate as the Dad. I currently have shared physical custody and retains sole legal custody. Do I have any right to legal custody of my son?

Yes, as the natural father you have joint rights.

I am not the biological dad.

Pursuant to NCGS 50-13.1 you may institute an action for custody since you have established a parent-child relationship.