I had my name changed at the age of 15/16 in the state of Minnesota. It was a breeze. I filled out "personal reasons", sat in the hearing area with a bunch of other people in there for traffic violations etc. Judge called my name, asked why I wanted to change my name, I said "It's what I've been going by for years, and it's who I'm in the process of becomming". He nodded his head, and that was that. Don't be nervous.