How common are missed miscarriages?

Shamar’ee • Mommy to a boy and baby girl

I had an appointment at the clinics for a free ultrasound but I guess they are closed for Presidents’ Day. Not sure why they let me schedule it, but anyway. I don’t have any cramping or bleeding but I’m so nervous my baby doesn’t have a heartbeat. I’m 6w 1d today. And my OB appointment isn’t until March 4