Stuck with dysphoria

Sorry for some mistakes, English isn't my native.

I feel so stuck. I know I'm a trans*guy since I was 12. Now I'm 17 and feel very dysphoric. My mother always has been the biggest fear for me. I mean she loves me, but when I was a kid she used to yell at me very often. Now it's ok, but I'm still afraid even to start conversation about anything. I see her as something like a god: I'm afraid to upset her and try to follow all of her opinions and thoughts. So, I can wait to come out till I'll be 18 in February, but i feel so dysphoric that it's hard to study and do daily activities, meanwhile i have exams this year.

I'm scared to come out and also afraid to shock and hurt her. She is very nervous because of many events in her life.

I tried to ask to cut my hair but she said "do what you want, but this will make me cry", so I don't want it to happen. Also I feel guilty because of lying, she doesn't know who I am.

I don't want to seem as a coward too much, when it comes to standing for myself with other people, I do it. She is my only fear. Couldn't you give me some support, please