Kristyn, It does sound like a missed miscarriage to me too. I had one in Jan this year. Went for the 12 wk scan to find out the baby died at 8 weeks. I felt something wasnt right through out the pregnancy although it was still terribly upsetting to not see a heartbeat on the screen. I was booked in to have a d&c the following week and started 'spotting' the day before.
Its a personal decision, but I chose to have a d&c because I didnt want to m.c naturally.