Miscarriage Rates

This might be a dumb question but I'm genuinely curious. When you hear miscarriage rates fall dramatically after 12 weeks, does that mean that you've bled and physically had a miscarriage by 12 weeks or the baby died by 12 weeks and you could find out much later. I'm just nervous because I will be 11 weeks tomorrow but I haven't seen baby since 8 weeks and won't see a Dr again until 16 weeks.