AITA for accidentally pushing classmate by trying to tackle school shooter?

So I was in English class when I noticed the quiet kid starting to sweat a lot, whispering to himself and get all fidgety. Now I'm no psychiatrist, but I swear I got a vision of him getting a gun and opening fire right there in the classroom, kind of like that one movie where they all die in the end. So I start paying close attention to him.

15 minutes go by, and what do you know, he reaches for his bag and pulls out a gun. Before he even gets the chance of firing the first bullet, I rush to tackle him. I honestly wasn't thinking straight. Looking back, I guess I just didn't want anyone to be killed or something, I couldn't stand losing anyone of my classmates.

The problem was, I accidentally slightly pushed back an innocent classmate who was in between the shooter and me by trying to tackle the shooter. I instantly felt bad but kept the plan of bringing the shooter to the ground before he could kill anyone.

Even though I succeeded in disarming him, I still felt bad. When everyone was thanking me and chanting my name while the cops arrested the shooter, all I could think of was how I accidentally pushed him. I told my volunteering group and the burned victims at the hospital I visit every single day and they all agree I did nothing wrong. I even spoke with the HIV kids after dressing like Spiderman and giving them toys and they agreed I did nothing wrong.

I spoke to him 3 days later after clearing my mind a little bit and he said, "Are you kidding me? You saved my life! I can't believe you feel bad about it. We all owe you, especially me after you revived my dad with CPR last year. I barely felt the hit".

I'm just confused... AITA?