NO, Nature will takes it's place. If you do do things that could cause a miscarriage it sitll may not and the baby would then have a birth defect, learning defect of somesort. There are other options if you do not want to have a baby. There is always adoption, and worse case an abortion.
At 40 weeks it's not called a miscarriage but stillborn. You will have to give birth as if the baby was alive. They will induce the labor.
Yes
Yes
Yes.
Yes.
Yes.
Yes
yes,miscarriage is a great risk of a 3 week pregnant woman.
No they can not.
Yes and even earlier.
If the doctor examined you after the miscarriage you are not pregnant anymore. He would've caught it. It takes several weeks for the hormones to settle so that might be it or you are pregnant again.
Possible if you took no protection and were ovulating.