''Just because a man glances up at night does not make him an astronomer, you know.'' (The boy with the striped pyjamas, p82)
What are you? A painter, actor, animator, musician...? Well, if so how regularly do you practise your skills/talents? If you get given a box of paints for your birthday, does that make you a painter? No! You've got to DO it to BE it! And the more you do whatever it is that makes you a creative person, the better you will be. Do it a lot, do it as much as you can.
On the flip side, if you DO paint, be confident! Call yourself a painter. If you DO it, then you ARE a painter, musician, animator, writer. It doesn't matter if you're at school or you work at Pizza Hut. That is not who you are!
So have pride in what you do and have confidence to be it. remember, you gotta be in it to win it!