What did I do to make him like this ? (Long)?

No horrible comments please...Right,My friend knew how unhappy I was being single and not having a guy to be with so she asked her boyfriend and he had a mate and said how me and him would go well together...anyway me and his mate started talking and we had so much in common it was unreal...few weeks later he told me he was falling for me and I was so happy...We then met up just me and him and he walked 3 hours from his house to mine just to see me and no guy has ever done that for me before. Anyway we took a walk to a lake and sat down watching the sunset..It was so nice and he asked me if we could kiss...but I said I wanted to take it slow so he was ok then so then we met up again the next day but with my friend and his friend and was going so well but then before they went home me and him kissed and I felt like crying because I was that happy but then I did not hear from him for weeks..he stopped texting me and calling me and he just ignored me...Then when we finally got back into talking I finally asked him if he still felt the same way with me and he said he fell for me at first but then it got lost and now he just wants to be friends. He don't even say hi to me anymore. I am so confused. I keep crying and everything reminds me of him. I was so relaxed with him and he was so funny and sweet so now I am thinking maybe it's something I did? I keep thinking to myself maybe I am a bad kisser so he gone funny? but surely guy would not act like this if I was a bad kisser... Please really need someone to help me here. By the way I am 15 and he has just turned 17