Right on sister! I used to work with teen girls, most of whom were "dating" older men, and most of those older men were pressuring the girls for unprotectected sex. Most of the girls I knew who did get pregnant were impregnated by older men, who were also working on other girls in the neighborhood. Lots of the girls shared baby daddies.
15 year old girls can be manipulative, but they're also terribly gullible, insecure and (just like teen boys) stupid with hormones. Then they get talked into sex, because "baby if you really loved me", or "here, have some beer", or maybe "i'll buy you this crap if you do this for me then you'll be popular because it's crap the popular kids have" or "i've got money, and can afford a hotel room which is a very adult and sexy thing to do" or "you're so special" and the next thing you know, you're 4 months pregnant with this dude's kid, and he's off banging your best friend because when you asked him to pay for part of the abortion, he said you were being "too clingy" and changed his cell phone number.