Chased by a girl with scissors at school

I've always wanted to share this with someone, because it feels like since the day this happened everyone around me has tried to brush it off, but it affected me deeply so here we go.

When I was young (maybe 11?) I was chased around school by a girl who I thought was my friend, she had a pair of scissors with her and was telling me to run because otherwise she was going to stab me. Now what led up to this? nothing. I'd gotten to school this morning, said hi to her and then we'd gotten to talking about the holidays, I said where I'd been and she told me I was wrong. This of course made no sense to me so I corrected her and said where I think she might have gotten confused.

She became furious out of literal nowhere. Asking people around us if they had scissors. Her mum told her to calm down, to which this girl flipped her mom off and called her mom all sorts of names, her mum rolled her eyes and left. In the distraction I'd stepped away from her and by the time she turned back to me the bell rang for the start of class. In full earshot of the teacher she told me to watch my back, that she was coming for me, that she was going to stab me, etc. all of which went ignored by those around us.

Then it gets to first break and whilst I'm standing with a couple of friends I see her walk up to us with scissors in her hand. We all get scared and start backing away from her, and that's when she starts running. She chases us through the halls shouting that she was going to stab us. Eventually we lose her by running into the principals office. We're all freaking out telling the principal what happened and it of course turns into a big incident. The girl got suspended and immediately sent home, I was young so most of what happened next went a bit over my head.

I do know what happened in the week that followed.

The girl during her suspension was given gifts to keep her entertained by her parents at home, in what was basically a little holiday. I on the other hand was traumatised at school.

During class I would get pulled out by my male head of year. To paint a bit of a picture, I was a tiny, skinny girl and he was a well over 6ft broad shouldered 40 year old male. He would take me to little rooms (most of which had no windows), he'd sit me down with himself between the locked door and me. He would then spend 1-2 hours shouting at me and interrogating me. "What did you say?" "You must have done something to provoke this." "People are like buckets filled with water, a drop can cause them to spill over. What did you do to her?" It went on and on, every single day. He was convinced that she was the victim, even though I'd done nothing to deserve this. Apparently I was becoming increasingly withdrawn at home which is how my parents found out and put a stop to it (no police were ever involved as it was apparently decided by all the adults that it would escalate everything too much.)

When she came back to school a week later I was told I had to reconcile with her, the typical hug and become friends again. My skin still crawls thinking about it. Fortunately she moved at the end of the year. She never apologised, although she did message me on facebook about 5 years later as if it never happened.

I developed major social anxiety both as a result of my supposed friend threatening to kill me and as a result of the head of years intimidation. I still see his blue eyes in my nightmares sometimes, and occasionally if I'm speaking to a guy with similar physical characteristics it's like I'm that scared little girl again. He really left the biggest mark on me. I feel like every single adult involved in this situation (from the principal, school counsellor, the teacher who ignored her threats, the girls parents, the head of year, and even occasionally my parents although I recognise the difficult situation they were in) failed me and were all so focused on what caused this "poor" girl to behave like this, that they forgot that I was the