Telling my parents..

I'm 19 almost 20 but I'm bot sure how to tell my parents I'm pregnant. They don't really approve of the guy I'm having my child with. I still live at home but I'm taking a full load at college and work 5 days a week. I'm an only child, so yes my parents are alot more strict on me than most. I have a feeling they will react horrible and I'm extremely nervous. Can anyone help? Any teen mom's been in this situation?