Why is it bad to have mental health on your medical records?

I recently was hospitalized due to mental health issues, I had to beg to get a ride from my parents to get to the ER in the first place because they don't believe that I have "good enough reason" to be depressed. during that stay, my treatment team told me that they were getting me into the Mayo Pain and Rehab clinic, that's what they had me sign papers for getting into. Last night while attempting to talk to my mom about my depression and my current feelings, she said that the hospital had me sign to get into the Mayo Psychological department for psych testing. She thinks I have munchausens because she doesn't believe I could be in this much pain and having all of these issues at my age. She's convincing my doctors that I'm not actually experiencing this pain, and they're agreeing with her. I don't know what to do anymore. I have no one that believes me, not even my doctors that are supposed to be helping me.

Does anyone else have medical trauma? I'm not referring to the events that put you in the situation. I'm referring to the mistreatment from heath care "professionals". this is a huge factor in my PTSD journey and just trying to find someone who understands. just for context mine was both with medical and psychiatric workers.

TW: My parents don't care about mental health. It was hard enough when it was just mood disorders (social anxiety/depression), but now, less than a year ago, my counselor diagnosed me with ADHD & mild autism (it doesn't feel official so I want to go to a psychologist; it feels wrong to say i'm autistic yet). My mom told me my social anxiety will go away by the time I graduate, but its worse than ever. My dad doesn't understand how it affects me and forces me to speak and yells at me for my faults that I don't have much control over (memory, losing things, not comprehending things and making simple mistakes/lack of common sense). My mom believes autism is caused by vaccines and that autism is an illness/bad thing. She's nice to autistic people, but she doesn't want or care to understand them or puts certain expectations on them (not acting weird or following social rules/norms). She and my dad don't know I've been diagnosed and I haven't fully accepted my diagnosis until it's from a psychologist. They aren't like abusive all the time. We laugh, love each other and try to have fun and hang out, but they don't want to know or understand their children. My stepmom even laughed when I told her I wanted to kms, her, my step aunt and step cousin. We get along now but I can't forget that or truly trust her bc of that. I'm afraid they will do my baby sister like that when they don't know how to handle her possible issues or that my brother will not get treatment and continue to be ignored. He has told me he's very depressed. I have selective mutism and I suspect he is suffering from it too now. We are somewhat similar, but were raised differently (he was punished more, I was more praised until a certain age).