TTC, irregular & 1 miscarriage

Erin • Married since June 2014. We`ve been TTC our baby #1 since then. This will be our 2nd child though (I have a step daughter)
I'm very irregular, usually get my period like every 60 days or so. My husband and I started trying to get pregnant right after our wedding In June, by August I took a preg test that was positive, then 2 days later I started cramping and bleeding. I went to the doc and it was an early miscarriage. Since then, 6 months later, I haven't been successful getting pregnant again and I'm starting to lose hope. I've been taking prenatal vitamins everyday since August. Does anyone have any suggestions, or similar stories that ended well?