Id guess that it is you AF. You only had the D&C a week ago but the loss was longer. Your HcG levels would have been dropping for awhile but just not quick enough for your body to know. Its now had that huge drop and it knows....pysically.... anyway.. to get on with its job! See this as a positive sign that the D&C was the right thing for you to do! Just make sure that the loss is not out of the ordinary and that there is no smell or colour change or clots.

Hugs!