I'm scared. Maybe because I'm disabled, and for the first time in my life I won't be able to call my mother and have her at my house in 20 minutes or less.

I think that is precisely why you should be excited! It will be weird at first, but you can call her as much as you want to, and you can keep your house however you want to, and there won't be anyone around to tell you not to where dirty pyjamas. :)
Chin up, it will be awesome. Unless you want to be told what to do for the rest of your life.
If you can't do it (but I think you'll be fine), at least you will have tried, and it's not like you just kept everything status quo your whole life.