Hi Sweetp - my Hcg at 6 weeks wasn't much more than what yours is - they had been doubling ever 48 hours and then within a week started doubling about every 72-96 hours (which I have since read/been advised is quite normal), I remember the last hcg I did I was expecting to come back at about 20,000 (or there abouts) and was only about mid 8000 - I was gutted and so expected it to be all over but am still going strong and 14 weeks tomorrow.
After the last hcg level - the mid 8000 one - I refused to have anymore as figured we are all different and its just numbers and I have read plenty of success stories DESPITE low hcg levels and just decided to go with the flow.
I know its hard but try not to worry too much about the numbers and more that they are increasing as the graph Nimbus posted shows.
PS - my last pregnancy (where I mc'd) my hcg levels at 6 weeks got nowhere near this this high.