Good for you, you addmitted you liked a younger girl. That is hard to do
Anyways I sort of know how you feel, there is this girl I really like and I feel like i need to talk to her, but she is in my class, and is the same age as me. But i feel the same way as you do for this girl. My "advice" is just to IM her, it makes me feel good inside. And today I was lookin at some pics of her and her friends, and they did a little "flash" and showed their bras, and I saw her, and I was just like "fuck, i want her so bad!" But the thing is she doesn't like me(atleast thats what she says) because she used to like me, and broke my heart one day. anyways sorry im rambling on again, so I would just say IM her as much you can, and try and get some pictures of her, that always helps.