Is it wrong that I stomped on a kids head because he asked me to he ended up getting a massive bruise and I nearly got expelled?
Why did you step on his head?
Because he wouldn't stop asking me questions and he wanted it
Even though he asked you to, it's still assault and potential murder that you followed through. He might not all be there, and it was irresponsible of you to stomp on him. Now you caused him so much trauma.
What's so bad about getting a bruise, it's fine the kid had it coming and his parents aren't like mine that cares.
You stating that the kid doesn't have parents that cares makes your actions even worse. You should never hurt someone, regardless if they ask you to or not. Your actions were wrong and could lead to you going to jail.