Miscarriage and now positive pregnancy test

Last August I miscarried at 8 weeks and it took doctors 2 weeks to rule out the possibility of viability. Those were the longest two weeks trying to figure out what I could of done differently and that this was my fault. Now 2 years after TTC and one miscarriage I am pregnant again about 6 weeks. I am terribly scared that it is going to happen again. Other than relax and not stress, is there anything additional I can do to limit the possibility of a miscarriage? P.s I have one daughter already 8 years old and doctors told me she was a miracle child. So that in itself is nerve wracking!!