Do I Need a D&C?

Hello. I had a miscarriage several months ago. I was 7 weeks pregnant and I was told it would all pass naturally. I had an ultrasound and the doctor didn't see any remnants. A friend later told me that even at 7 weeks my miscarriage requires a D&C.; She said that after her first miscarriage she had two more and it wasn't until she got a D&C; that her pregnancy went full term. I went to a free clinic because I was unemployed at the time. Is it possible that my miscarriage wasn't treated properly?