The doctor rang back quite late and the test on my haemoglobin (iron levels, etc) came back ok. As far as organising a D&C, his opinion was if I had bad cramping pain or heavy bleeding, to go to hospital (and have D&C), or I could wait to see the results of next Wednesday's ultrasound and check hCG levels again next week, then arrange a D&C if warranted. Or I could ring the obstetrician I'd initially arranged to see and ask what they thought. Of course, it was too late to speak to the ob. so I've left a voice message. All a bit up in the air. So I'm not going to worry unless I suddenly get bad pains prior to the ultrasound. I'm going to hope that everything will be clear by then and that my hCG levels are back to normal pre-pregnancy levels!
Thanks for your responses Amy and Lisa.