Young moms?

Any young moms have any advice on how & when (currently 8w5d) to tell my mom? I'm 20 (will be 21 by the time baby is due) and had an abortion when I was 18. I'm scared my mom will tell me to make the same decision however this time I'm in a healthy relationship, and both me and my boyfriend are super excited! (I was in a abusive relationship at the time of my procedure) I know I'm still young however I don't want to make the same decision because it has mentally and emotionally effected me to this day. I'm so scared, please help!