Even though both of you are legally children, there are a few things you need to understand about statutory rape. Many states make a legal distinction at the age of 14 and in relationships between children where there is a 3 year or greater age difference. So legally, if her parents got pissed about what may or may not be going on between you two--which they probably would given that you're both girls--you could wind up in MAJOR trouble, like juvie, etc.
So, yes, this is probably legally a very wrong thing to do.