I need help

I've been trying to have a baby for 2 years. I had a miscarriage July 26, 2015. Was that it? Am I dried up or something? Is there something wrong with me? The doctor says I can have kids because I'm only 20. Ice been married for 2 years, no drugs, no drinking, no smoking, I don't do risky shit and no matter what, its never a positive... Please, if there's anything I could be doing, don't hesitate to say