17 & Pregnant

I'm 17 years old and got unexpectedly pregnant. My grandma, who also so happens to be my mother, is real strict about this kind of stuff. My aunt got pregnant around the same age with her first kid and I asked her what my grandma's reaction was and she told me that she was on the verge of getting kicked out at the time. So with that being said I'm scared to tell my grandma. I'm 7 weeks & 1 day and I don't know what to do. I'm supposed to be moving out soon with my boyfriend and the plan was to wait until I'm officially moved out to tell her but the moving situation is taking a little longer than expected. I know if I wait any longer it'll just make things worse. & I won't know until I tell her. But I don't want to get kicked out considering that I don't have anywhere to go right now. Can someone give me some advice?