Hey Pandas, Aita?

So, my brother (11m), let’s just call him “Steve” keeps being mean to me and acting like I was being mean first, and I can see his side of the story, but I need some second opinions. To set the scene for some of it, earlier today, Steve was trying to scare our chickens. He was running up to them and jumping at them, so I grabbed one of them to keep it safe from him and tried to scare him off, and he got angry, so he whacked my glasses off my face. Mom saw it and scolded him a bit, which made him more angry, so I retreated and went for a run around the block. When I got back, he was angry and thought I was being mean to him for “yelling” at him. (I was just growling.) I feel like he’s being really mean, but I’m worried that I’m being a gigantic asshole for starting this thing. This is the most recent of many events like this, getting closer together and more problematic. He’s already sent me his first hate note, and I’m worried that if I stick around, I’ll end up being more problematic. I know I’m victimizing myself and shouldn’t be a crybaby about this, but I’m seriously considering running away. I don’t know what to do, I feel like I’m just stuck in a downward spiral of insanity. He’s ruining my self esteem, making fun of me for having no friends, and I just want to escape this hell. I know I’m exaggerating and making it sound worse than it is, but I don’t know how much longer I can do this. So, AITA for starting a bunch of conflicts with my brother?