Okay so here are some important things if this was brought to the police or court.
1. You should definitely try and keep digital and probably physical records of your home situation. Meaning that you need to have some sort of evidence of the incidents if this was brought to the police or court.
The point of both physical and digital evidence that if one was destroyed you would have backup and you'd still have your proof, as well as more evidence in multiple mediums means better case.
physical being on a phone/camera, tangible photos. Digital being audio recording or all the other stuff but on a drive or in the cloud.
2. Also have verifiable proof of your mothers stability (This goes in-hand with #1).
Also I understand the want of protecting yourself from your mother if she gets in a fit of rage, but if that's how far gone it is that you are worried that you will have to end up protecting yourself from her than you need to go back to 1 and 2 and bring these to the police or something for child endangerment, or domestic violence etc.
I advise not physically harming her because she could throw it back at you for a charge of assault or domestic violence as well.
I don't know how much of a connection you have with your mother but if it's as bad as you're saying you should get some help. Really good luck man, keep posting and let us know what's going on.