Just can't get pregnant

 I'm new to this. But just wanted to express myself a little because I don't talk to anyone about this. I think I may be stressing myself out because I've been trying to get pregnant for about two months now. I have been pregnant twice before but ended up having miscarriages and that was with a different guy.  Now I'm married to another guy and just can't get pregnant for nothing in the world. It's so frustrating and it makes me sad every time. All I want is to have a child of my own someone i can call mine😔. I follow the ovulation calendar and have sex when I'm fertile and ovulating but I still end up with negative tests and a period the next month. I just don't understand.