OP, this is not your fault. This guy is a pedophile and groomed you into having sex with him. He prayed on a vulnerable girl because he is a lowlife. He isn’t your boyfriend, he’s your rapist.
Your brother is doing the right thing by telling the police. This guy deserves to be locked up in a prison cell and have the key thrown away. When the police talk to you, tell the truth. There’s no reason to hide anything. Justice will be served.
Yeah that’s a crime and he should be arrested for pedophilia. You’re a child and he’s an adult and should know better than having sex with a minor. This man is grooming you, and it’s gross, save yourself and stay away from predators. There is no reason a 21 year old adult can have for having sex with a minor as young as you.
Yeah your brother should definitely call the police you have basically been raped no matter how you look at it.