One shot - an eye for an eye

Hello ! As a non native english person we were asked to write a short story about gun violence and mass murderer so this is my work.
TW suicide, depiction of murder and mention of self harm and bullying
Enjoy and feel free to write reviews and to report any mistakes ;)
I also "borrowed" some sentences of a book maybe you can guess which one (tbh I don't even know if this is legal (if not plz warn me) to steal bits of a book but meh)