It is normal that you want a baby, especially after loosing the last one, and it sounds like you have thought this out. But I was wondering... Is your boyfriend on board with this? It sounded like last time he wasn't very supportive, and you really don't want to have a baby with a boyfriend that doesn't want it.
Don't worry, if you were able to get pregnant before, even if the baby wasn't able to live, you are most likely still able to get pregnant.
I think that you should wait till you get married before you have a baby, that is the only way that your baby will truly have a stable life.
But whatever you decide you can get support on here.

Let us know how everything works out!