I am confused about my friend younger than me? I am confused on all my other "friends" too? Help?

Aw, don't worry. I know how that feels man. Relax, she might have a lot going on right now. Who knows it may be school, family, other problems, PMS, etc. etc !? She did reply so that shows that the relationship is still mutual and don't worry about it. And remember a good friend is hard to find, diffucult to lose and impossible to forget. That friend of your will come along someday. Just give her sometime and wait for her to reply. :) hope things work out ! all the best.