Christian but don't believe in god..?

Hello, I'm a 13 year old girl and I got baptized at around age 8 and I'm getting confirmed soon. I do not believe in god and haven't for a while. I'm agnostic. I haven't told my friends or parents yet because I'm scared what they will think of me. Is this bad, getting confirmed when I do not believe in the Holy Spirit? I realize I could tell my parents that I don't want to, but I'm scared.