Shan, push for a scan but if they won't do it, can you get a private scan asap?
Just to ease your mind. A miscarriage at this stage would mean debilitating cramps and huge blood loss. This is far more likely to be due to the increased blood volume and an irritation somewhere inside. Its highly likely there's been a bit of a bleed in your vagina somewhere that's clotted well, but for whatever reason, the clot has broken up and moved and the source of it has bled a bit more, hence little clots and fresh red blood.
Please try not to panic, no cramps is a very very good sign. If you have a doppler, leave it well alone though, they should not be used for this scenario. If you want reassurance, go to A&E or to a private clinic.
I'm sure all is fine, but have a big hug anyway xx