depends on which state your in, cuz the legal age of consent changes, look up the age of consent in your state, if it is 16 or under then no they can't do anythign to you legally, you cant go to jail or get fined or anythign like that, but if the age of consent is 17 or over, then they can press charges no matter if it was consentual or not and u'll go to jail, she doesnt even need to testify they just need ur dna