Invalidated by my teacher for presenting on hydrocephalus

I completely relate to this, I'm 18 now, but a few years ago when I was in school I had a pass that allowed me to leave lessons 5 minutes early so I could get up and down stairs before the rush. I had a few supply teachers accuse me of making a fake pass and wouldn't let me leave. On another occasion a teacher asked me why I had the pass and I told them about my hydrocephalus and dandy-walker syndrome and they accused me of making up medical conditions!

Its not made up, its very serious