It's not about making what your create the best it could possibly be. It's not about trying to be better than your friend or the cool kids. It's about doing your work because it brings YOU happiness, joy, desire and motivation. If you like to doodle, then doodle! Don't stress yourself out over messing up. If you like to do math problems, heck do math problems. And don't worry about getting answers wrong.
You can't tell yourself you aren't good enough, strong enough, creative enough, intelligent enough, whatever ______ enough. Because the last time I checked we don't have to prove anything to anybody. We are here and we are designed to create. To use our brains, our imaginations that we are gifted with to create with our endless possibilities. To be free and open and courageous, to take the ideas we get delivered to us and run with them. Do anything with them. Don't be afraid, be courageous.
Even if your final product doesn't turn out the way you wanted it to, even if you think it looks awful, hey, at least you TRIED and you didn't just give up and walk away. You created something. And its of worth, even if you don't believe it.
Not everyone is going to like you. Not everyone is going to like what you create, what you say, what you do. And that's all the more reason why you should do whatever the hell you want and mind your own business, okay? You are the creator of your life, you are the controller of your happiness.
Now, go and do what makes you feel AMAZING TO BE ALIVE!