“I think I can” Then why not? What is holding you back? The problem is that you only think that you can, rather than knowing that you can. You do not know your Self. You do not know your potential. Something goes wrong and the first thing you do is ask a friend for advice and not your Self. Why do you feel more satisfied when someone says “O you look good” or “nice dress”? Why do you depend on your friends to make you happy? Why do you feel intimidated when you see someone “cooler” than you? You just think that whatever your friends say about you is who you are. They are the ones you look up to. If they dress a certain way, you also have to dress the same way. If they listen to a certain type of music, you also have to listen to the same ones. Maybe there is nothing wrong with that. But when you give the most preference to your friends you tend to ignore your Self. You forget to see your perspective.

“Have you ever taught, counseled, advised, or comforted another person? Have you responded to a child's question? There's your wisest self, speaking out. Your wisdom will never be perfect. To think so would not be wise.” Elaine Aron, Ph.D (research and clinical psychologist)
Don't think you can. Know you can.
Try to listen to the inner You. I am sure you will be surprised.