Yeah, what this guy said.
I had a msicarriage in August and it freaking sucks ass. Since I'm guessing she's never had a kid before, I'll describe it this way:
It feels like the worst cramps possible. I felt like a fork was shoved into my uterus and twisting.
I did not get a D&C - I chose to miscarry at home and I went to the doctor the day after everything had passed. The baby was the last thing I passed. We chose to bury her (we think it was a girl) and since there was no birth or death certificate (too preterm to have that), we opted to bury her at my in laws, in the country.
My doctor said that at 14 weeks, most women need a D&C, but I explained to him that I felt the need to be at home, and he understood that. It's not necessary to get a D&C. I went in the day after birthing the baby because I wanted to be sure everything had cleared my uterus. The doctor gave me the 'all clear' and I had some minimal bleeding over the next week or so.
This IS a birth. Most people don't realize or understand that. A miscarriage is an extremely preterm BIRTH. There is a baby. It died.
Treat your girl very gently, don't tell heror expect her to just be over it. It's not just a lot of blood. She was probably very attached to that child already.
Be kind to her. Don't tell her to get over it. Let her cry.