Placenta previa

I can't stop worrying about having complete placenta previa. My placenta is laying completely on the bottom of my uterus and my cervix is almost directly in the middle of the placenta. I'm so scare sit won't move. I'm 15 weeks today and my dr has expressed how careful I need to be. She had her nurse call me twice in one day to talk to me about it. I have to wait 5 to 7 weeks for another ultrasound and it's eating me up. My aunt had placenta previa and she almost lost her life. I can't stop my mind from wondering. Help me