Advice please

Hello, this is my first time writing a post on here and i don't know if people will read. Diclaimer english isn't my first language so if I make some mistakes please forgive me.
I am in need of advice for something that might seem really childish but is really important to me. To give some context i didnt receive a diagnosis yet but i am in the process of getting one, however the professionals i have been talking to are pretty sure i have high-fonctionning autism and ADHD and I am also pretty sure of it. I am a almost 20 y.o girl still living with my parents and 2 younger brothers and i am black (it matters in this).
As for the issue that brings me here today, it is about my phone. It sounds kind off stupid but it matters to me. For me, my phone saved my life and is the only thing keeping me going really. It is really difficult for me to create relationships and also to keep them, and for that my phone is a great help. After graduating from highschool, all the friends i had managed to make went abroad for their studies while i stayed in the country. The only way to maintain these friendship were texting them with my phone (because calling is a little hard for me). I work very hard to maintain these relations.
My phone is also the distraction I NEED to stop me from having panick attacks everyday or to help numb out the constent noise in my head from all the thoughts that never stop. It helps me take my mind off the things that make me want to end it all. It distracts me when I'm walking on the bridge above the highway on my way home. It distracts me when i look at the bottle of pills for too long. It is what helps me fall asleep at night. My point is that it distracts me from stuff that stress me out too much.
I CAN'T talk to my family about all these things, so of course they don't understand why i use my phone so much. They think it's an addiction and it might just be but that is what i need to be okay. I am very aware that it is a problem and I am trying to find new ways to cope, new hobbies and all but it takes time. Which my parents don't want to give me anymore.
Today they announced to me that they decided that i couldnt have my phone with me all the time. I can't have it in my room at night, I can have it max 2 hours a day with supervision and that as of tomorrow morning at 10 AM. They say "It's for your mental health, me and your dad don't sleep anymore because we are so worried". Ok fine but when i try to explain why it is not possible and actually not good for my mental health, especially so abruptly, they shut me down. I apparently don't have a word in what's good for me even though I am an adult (not very good at it but still).
I am not sure how to handle this without getting furious and crying since I am not very good with words or talking. I hope i can get some advice on how to act moving forward and on how to make my parents understand that this is going to cause me more pain than good especially right now. Or maybe I am being dramatic because I am emotional since this just happened 30 minutes to 1 hour ago. I hope I can get some good advice on here, thank you for reading. Again sorry if there's alot of mistakes

UPDATE: My dad just walked into my room as i was about to post to tell me that I don't have autism, that I'm faking it because I'm smart abd i read too much about it (?)

Again sorry if this doens't make any sense.