"i shouldn't have to experience that."
yes you should, actually. that's life. upsetting things happen. no one should have to experience any discomfort. but we do. we get stung by bees and sunburns and headaches. we live in bodies in the world.
autistic people are human beings who have the right to exist in society, including during meltdowns. having one class of your entire semester interrupted by a singular meltdown is not anymore of an infringement upon your entitlement to education than having your class interrupted by a fire alarm or cancelled for a snow storm.
one of my peers once experienced a cardiac event 10 minutes into class. it was terrifying. it was desperately upsetting. i was contacted by the school and offered counseling because i happened to be the one who managed the situation until paramedics arrived. everyone was worried about my classmate first and foremost, and then about me. no one blamed anyone, and certainly when my classmate happily recovered and returned to school, no one thought they should be removed from the program.
the difference being that people believe a disabled personal, especially with cognitive disabilities, in crisis are not experiencing something outside of our control, but instead that we are in fact making a choice to make a scene, out of malice.