*iz confuzzled*

A new semester is on the horizon and I'm supposed to be starting my grad classes. For the past few years I've been telling everyone I'm in a 5 year Masters program but it really hit me recently that I'm going to be going to graduate school and coming out with a Masters and then I have to get a job! I hope I'm not the only one who feels like they have no idea what they want to do with their life and feel like they are on the fast track to an unknown future. I wish I was the person in 3rd grade who knew exactly what they wanted to be on Career Day. I wish I had planned out what college I was going to attend and made backup plans for my future. But I'm not that person.
I have to know what I'm getting into before I commit to it. I hate uncertainty and going into this career headfirst with no introduction to "real life" is just so mind-boggling for me. Sure I have an interest in the field and it's a possible carreer but I don't know if I want to do it for my whole life. Maybe it's because I'm a little younger than all of my friends or maybe I'm not as mature...I don't know but I still have dreams of travelling and living in the big city and wanting to work on a movie set. It just seems that I didn't let those wants rule over my head at application time and it feels like I got thrust into this course unprepared.
Why do we have to decide at 20 years old what we want to do until we're 60? Why is it so bad to "think of life as a tv show" (like my dad always faults me on)? Real life is crazy and sucky enough so why not let your minds escape into these worlds where heroes and the like do exist?