Okay, I'll PO the right to life crowd with the first part of this, but the long term implications of either actually bringing this child into the world(is abortion a legal choice at this point?) or not putting it up for adoption are simply not good for either you or the mother. Yeah, a few couples have babies very young and go on to lead successful lives, but many of these only because their parents look after and provide both time and money in this effort. Most child parents struggle in poverty for a long time for their choice - if they stay together - and most don't. They don't continue their education because of the need to provide for baby, a large portion of their income is spent providing for it, mama doesn't have time to work, her work becomes a zero net-sum game barely covering child care costs, and so on. The reality of it usually sucks.
This may sound really cruel, but as you asked for legal advice, unless your parents and/or hers are ready and able to foot the bill, get rid of the child by any legal means available. Abortion or adoption.