help! I'm pregnant and no one knows

How do I tell my mum I'm pregnant, I'm only 16 years old and start having sex with my boyfriend 3 months ago, to my surprised I've found out I'm pregnant...my boyfriend broke up with me as he said he wants nothing to do with me now. I'm really scared and I don't have many friends to talk too, I really want to tell my mum but I'm scared she'll kick me out... how do I tell her? Has anyone been a teen mom?