I'm pregnant.. at 15.. how to break it to mum dad and bf?

Just don't do what my sister did. She kept quiet until she started showing! My parents didn't take it well because of the way she did it. If I were you I'd first talk to an adult I trust, such as an aunt, best friend's mum, pastor, whoever. Then get that person to go with me to tell my parents. Also, research pregnancy and parenthood, so you're informed. Then you could speak to them using facts, like "look, I know that it would cost about this much each month to take care of my child, but if I do this and that, then I can more or less cover things" If you are practical and prepared, then it proves to them that you realise that you've made a mistake, but that you are mature enough to deal with it. And if they react negatively, just remember that they will come around. They will be shocked, but once reality sets in, they will support u like u won't believe!