AITAH for saying my leg hurts while my brother said the same thing before me?

This would be confusing out of context so I'll give you the prologue to this case.

Me (18F) and my brother (12M) aren't in good terms with eachother. He randomly started calling me names when I was in the same room as him, especially "monkey" or "maniac". I simply thought this was funny and joked back for the first few times although I didn't like it. I have told my parents multiple times to make him stop this because I don't like it. They all just said to stop and be the bigger person. I try to be the bigger person by ignoring him. But it's too much, he's gone to the point of not wanting to sit next to me in the car or anywhere. I try to make conversation like normal with him but he'd never say anything of use, it's always "monkey" or "maniac" or some other word to insult me. Sometimes when I talk to someone in my family, he just pushes me out of the convo and tells me to shut up. It's like I can't speak when he's in the room.

So we get what kind of problem this is so I'll continue to the question. AITAH for saying my leg hurts while my brother said the same thing before me?

Idk if this part is important but I'll add it nonetheless for you guys to have the whole build up. Today we went to a little concert for my siblings' (including my brother's) music class. Everything was fine since he was performing so he had to stay away from us (my mom, father and me). Once it was over, we went home by car. He was asking for 10€ to hangout with his friends the next day. My parents can't give him the money because we were not doing well financially. Even though my mom made it very clear to him, he still kept on pestering. I told him that he can't get 10€ atm because we're clearly in a tight situation. And there's no way for us to magically get money from thin air. We're already home by that time and he was still continuing to ask for the 10€ Once we got home we were fine and laughing about a joke someone made. I finally took off my shoes because I've been walking the whole day pretty much. It hurt so I said "My legs hurt" Welp unluckily for me, I said it at the same time as my brother. And he started getting angry at it and saying "are you mocking me?" And telling my mother to blame me and teach me a lesson. And she was mad at me. Telling me to stop acting like a kid and ignore him. And my father was saying the same and even told me to not talk at all. Ig I'm supposed to be mute from this day on then? So, am I the ahole?