Miscarried March 4th at 4 weeks & 4 days

My husband and I weren't planning for me to get pregnant for a couple years. We are both 24, just married in 2014, and we were super scared. After a couple days, began to get more excited. We found out February 24th that we were expecting and that Sunday I suffered from cramps and lots of blood, and went to ER on Monday only to find out I would probably miscarry. My HCG levels were 119, then on Wednesday 113 (dropping slowly). Friday, March 4th I passed a lot of tissue and clots, I knew that was it. Since then I've felt myself become depressed, fatigued, and wondering why. Wednesday I went in for blood work and it dropped from 113 to 23, confirming the miscarriage.We had sex Yesterday and all I could do was cry. It was the hardest thing that has happened to me, and I want to start trying again as soon as we can. My husband says he wants to make sure I'm healthy enough to get pregnant. I'm just scared it will happen again. I know God has a plan, but I wish there was something I could do to have kept the baby. Any words of advice or suggestions would be appreciated!