I am in real danger! PLEASE read and help!?

this is real I really need help. well today I was asked to do something for someone but I said no and then I was asked to meet them and I also said no because I couldn't and I really couldn't but If I could I would have but I really couldn't so then they said theyre going to stab me but obviously they could get more out of me as I am a girl and they realised that, so they said theyre going to kidnap me and rape me and I know the people that are saying this and I really know that they would so please help what should I do ?! and I cant call the police or tell my parents because my parents would make me call the police and if I tell the police theyre more likely to get me and kill me or something for ratting them out . please help !