3rd miscarriage at 19

The other day I was posting my bfp and being all happy told my boyfriend he was happy .I was gonna give my nephew/godson a little cousin to play with .they would have been exactly 1 year apart but all that came grumbling down when I started bleeding a few days later. This is now my 3rd miscarriage I had 2 at 18 year old.. what's wrong with me I thought young adults had a better chance for having a healthy pregnancy .. I'm broken I feel like my body is broken.. I dont know what's gonna happen from here now but good luck to the people trying and I hope you have a healthy pregnancy and a healthy baby