If I was arrested as a minor, can I still apply for citizenship?

I came to the USA as a child in 2005. In 2009, my mother's boyfriend violently bit my hand and so I called the police. When they arrived my mother lied to the police to protect her boyfriend. She stated that I punched him in the face, I was 15 years old at the time. They arrested me and sent me to JDC. They arrested him and took photos of my bruised hand for proof that he had bitten me. He spent a night in jail and I spent a week or so in JDC. I am now 23 years old and have moved away from my toxic mother. She has admitted to me many times that she did lie to the police because I did not punch him in the face. She said she was sorry. When I went to court at age 15, I was scared and ignorant. They appointed me a lawyer and I only got to talk to him during the court hearing. I told him I was innocent but he told me I would have to go back to JDC for a longer period of time for another court hearing. He advised me to plead guilty of domestic violence. So I did, I was charged with a misdemeanor and was sent home that day. Like I said, I'm 23 now and want to apply for my USA citizenship, I've read other posts saying this may impact my good moral standing however, I believe I am a good person and was charged wrongfully. Do I need to get a lawyer? Where can I get free legal advice from? Will they refuse me? Like I said, it happened within the first 5 years of me living here. Please help. This happened in one state and now I live in a different state.