Following your heart

Are you happy with what you are now?
I expect a " No" from most of you. Certainly I am not!
I have always had an interest in Astrophysics and wanted to pursue my carrier in that field. But everything doesnt work the way you like, does it? My interest in this subject started while I was in 9th std. My love for that subject was so great that I couldnt imagine myself in any other position. I used to tell my parent that I dont need a job or anything, just give me a room with a computer and lots of books on astrophysics. My parents were very supportive, but it turned out that I was not upto the level required to be an astrophysicist.
It was not very hard at that time as almost all of my friends got into engineering and I choose to be one among them. But when I think about it now, I feel like a loser- someone who failed to follow his heart. This creepy feeling started after reading the really wonderful book, The Alchemist by Paulo Coelho. If you have read the book, you will know exactly what I mean. In simple words it about following your dream and everything around you act in your favour if you try really hard. Though I dont believe in the second part, it really makes me sad.I feel like having an empty space in my heart weighing me down.
But later I found out I wasnt the only one with the same problem. One of my friends from college has the same situation or even worse. He is someone you call a versatile genius. He can sing, dance, write, act- i cant find a thing he cant do, except of course study. He once told me about his dream of joining an arts college. From his expression I could find that he was not at all comfortable.
But there are still another group who does have a real ambition, who go on with their life as it is. I think its better to have no dream at all than mourning over it. What do you think?