I don't think I've ever been traumatised but I feel like this is closest I have come to it?

I've never posted before and I'm really nervous to do this so I don't want to write too much... I guess I'm just going through a bit of hard time and since I have no one to talk about this with, I might as well just spill a few things here, they might not even make sense honestly.

My mom had an accident a couple weeks ago and its not the first time but she was shaking violently on the floor and couldn't bring herself to even get up nor even say anything. I'm presuming she had a panic attack which makes sense as my parents were in the middle of fighting when it happened. They both said things to me that have stayed part of me since but what affects me most is just remembering holding her in my arms like she's going to leave me forever. Whether its because she's done with this hellhole of a house like she said or because she's actually going to die. That day, it was 5 in the morning when they started fighting and I was trying to ignore it while I was eating and getting ready for school in my room, but my dad came bursting in and told me my mum needs help. That's when I see her shaking visibly on the ground, unable to speak or move. The words that were said there will never get out of my mind...

I don't understand why me, a mere teenager who already has so many mental problems herself, has to deal with all this. I just feel like an adult right now with two parents who are basically back to being children. I watched my mom cry as she told me doesn't want to be an adult anymore and wants her own mom. I want my mom back too, she's not there anymore mentally. Even though she still takes care of all of us, she really isn't there. It pains me to see her like that, starving herself because she forgets to take care of herself. It's like we both switched places because I was just like that too.

I can't even sleep at night properly because every time I hear my parents muffled voices coming from their room, I feel like its going to happen again. I even started desperately writing in this forum because I just felt that terrible dread of feeling just now. What's even crazier about this is the fact that I found a way to escape all of my problems at home temporarily by staying somewhere else far away in a family member's home, so I'm not even with them, but I'm still reminded of them. There were people only just talking in the other room and I froze up preparing for the worst. I'm sorry for saying all this and I feel a sense of shame writing this and I have no idea if I really should be doing this.

This seems like a terrible idea, I haven't even shared the worst of my problems but I'm already regretting it. If you read this, I'm sorry for the dumping and I know its what everyone has to deal with but I can't handle my own parents letting out their rage on me and expecting me to keep my family together just because I'm the oldest. This probably makes no sense since I'm so sorry.