I was about your age when I was seriously thinking of converting to Islam. I've seen so many faboulous sites about the miracles of the Quran and Sunnah. Being a fan of maths, they really impressed me, in a special, kinda mystical way. I've also checked the pictures of Allah's name in nature and, in the general feeling that Islam is the truth, found them amazing.
Then a week passed, I rationalized myself, checked other, non-islamic sources as well as non-exaggerating islamic ones. I find out that there are plenty of miracles in other religions and the mystical feeling went away.
I was raised a Christian, became an atheist at about 15, soon switched to more reasonable agnosticism. Then I had the islam-week I just described and have been an agnostic ever since (for almost a year now).