What will my future lead to?

So I'm at the age where I need to be making important descisions, GCSE's coming up, sixth form soon, part-time job maybe and hopefully University!
But what do I want to do when I leave school? If I'm honest I have no idea. Which sucks! I would love to do something in art, but my Dad said theres not much pay, so that went down the drain. I was thinking of becoming a doctor because it would be sooo heroic to save lives everyday, but I just can't do science as well as I would like. Maybe a Counciler ? But wouldn't that be soo boring. I would also love to work with animals, but seeing animals in pain most of my working days.. I just couldn't handle it. So I'm pretty stuck. What the hell do I do after leaving sixth form lol?!
I know what I really want to do though...My dream I guess! But it's prettyt hard to get in to, adn even if i do manage it might not be as good pay. My dream career is singing. I know so many teens can say that and all the "I just want to be famous and marry Brad Pitt" crap, but i really have no other career interest. I'm not the best singer.. but I've heard worse lol (without chuffing!).
But really.. I have to make a different choice and be unhappy with my career chouce for the rest of my life.
Any advice? No? Hmph...