Ultimately, YOU will have to make the decision that is right for YOU.
I do suggest you tell your parents and I suggest you get counseling from an impartial person who can help you determine your best choice (keep in mind that none of the available choices are good ones).
Also, please be responsible enough to make your choice well within the time window recommended so that IF you choose abortion, it will be done within the first trimester (hopefully as early as possible).
Honey, nothing you choose will be easy. I know, as I have been there (well, aside from the smoking and drinking).
Please take care.