Nice choice of a name...Amy. My ex wife's name is Amy and it caught my eye.
You know, for the length of time you have known the girl, it sounds to me like things are going great, except that it sounds like you want more. Once you feel comfortable enough around Amy to talk to her about this subject, then do just that...ask her about it. But first, you have to be honest with yourself about what you want, and what you are and are not willing to accept in a relationship. Be ready though, to hear something you may not want to hear. She may not want to go any further than where you two are right now....so you need to be ready if she says just that. Honestly though, what's wrong with taking things slow, and seeing where they will lead? Try a nice dinner one night, followed by a romantic walk, or something of that nature, and try kissing her.
See if she responds, or turns her head...that too would be a pretty good indicator (as long as you didn't have anything with garlic or onions for dinner !!
)
In short, communication, communication, communication.... Talk to the girl, and you will be glad you did.
Good luck