Be careful of going too fast.
There are things you need to learn through experience about "being". If you pressed the magic button and one day woke up in the other body it would be, in my opinion, a disaster.
How to walk, talk, interact with people, experiment with clothing styles, hygiene, gender specific protocols, etc Guys and gals are treated very differently in society. Getting used to those differences is part of the transition for both you and those around you.
Your mom's actions stink and she's putting herself first. Do remember that this is VERY hard for our loved ones. You've been thinking about this for years (? Decades?). She has not.
One thing I can say is that once you do have facial hair she will be starting from square one on pronouns. You might want to explain to her that this time is for both of you to transition and if she doesn't start now, she will be a year behind everyone else.
Let us know how things progress. I hope it gets better.
Sent from my LG-H910 using Tapatalk