Can't handle miscarriage

I had a miscarriage Friday while I was at work, I didn't even know I was pregnant until I seen my little baby laying in my underwear. I just had a baby in December and had my depo shot February 13 and I don't know why my pregnancy test didn't come back positive. My husband wanted our children to be back to back and I wanted to wait until our daughter was 4/5. Now I just feel absolutely terrible for telling him I didn't want another child while I was already pregnant again, I know it's stupid but I feel as if I'm the one that caused it. My husband cried when i told him but now he won't talk about it, he's trying to be here for me but I don't know how to handle this.