hun
id suggest talking it all through with your parents. How far are you into the pregnancy?? Sooner or later they will notice. As with your boyfriend you cant stay with someone your not happy with. No matter wether your pregnant or not. It wont work if you dont have those feelings.
I really think you need to talk to all thats concerned. I was 20 when i fell pregnant with my son and had to do the same whole speach with my father. I know its not easy but you can get through it with the right love and support x