The pressure of "So what do you want to do with your life"

The question "What do you want to do with your life" is a question that every teenager and young adult knows incredibly well. At the young of 12 you reach secondary school and this is when the question begins to all any adult ever wants to ask you, it still baffles me to this day that people expect a 12 year old to have any idea of what they want to do other then be rich and famous. I am 20 years and I still have no answer to this question and it makes me feel somewhat of a failure, as a child you figure that by the age of 20 you will have both your life and career planned out. I know what i enjoy doing but I am not sure if I would ever be able to pursue my loves & hobbies as I have no idea of how to go about it, besides a career in listening to music and watching YouTube videos seizes to exist (at least to my knowledge). When I am asked this question my first reply is always I haven't firgured out what I love to do enough to do it for the rest of my life, to that I am met with "You just try it and you see if you like it" and "your young just try different jobs and you will find something you like". In my lifetime I have seen the effect that hating your job can have on a person, it can drain the life and soul out of a person if they don't get out in time (most don't). I am fully aware that everyone feels that they will be exception and hey will find what they love and spend the rest of their lives doing that, but I feel that I will and that I won't settle with spending my life doing a job that I hate simply to pay the bills. 

The one thing that I am sure of for my career is that I want to be my own boss, the thought of having to work for someone else and work by their timetable and their rules is like hell in my mind. I want to be able to decide when I work and how long I work for, I want to be able to be as free and creative as I want without having to have a person above me approve my work. So in all honesty I guess my future response to "What do you want to do with your life" should be ... I want to be my own boss.