There are too many questions before you start HRT, it is normal to have that in your mind for a long time, you are moving into a new direction and giving a really big step forward, you will be thinking about what could go wrong or right, you will think about your parents, friends, work, etc.
You need to breath and organize all your thoughts in your mind, in my case i had some questions in my mind before i started HRT, and the questions were "am i ready to lose everything i have accomplished so far and fight for the person i really am? Am i ready to tell everybody that i am really a woman and that everything else i have done in the last 35 years it was just an act? am I ready to lose my friends, family, work to be happy?"
I knew i was ready once i answered that questions.
Good luck, be strong, remember you are doing this to be better and to be happy, many things could go wrong but no matter what be strong and always be you!
And remember, you will always have people that will listen to you in this forum.