Irregular gestational sac with no embryo

I went to the doctor last friday and had a slightly irregular gestational sac that measured 6 weeks. there was nothing to be seen in the sac and the doc had me do hcg level testing. on monday the levels showed 17,671 which i looked up and are in the normal range for 4-6 weeks. i had more labs done today(weds) but havent gotten the results. i am having a hard time fining information on irregular gestaional sacs (its like an egg but slightly caving in) i very worried has anyone been through something similar?

[KATE535]

I have no personal experience of this but I have heard that you need to be more weeks than you are to see things clearly on an Ultra Sound Scan. The baby may be better visible in a month or so, so try not to worry just yet, you are still VERY early in your pregnancy. Try to stay positive for a few more weeks. Don't think the worst. Good Luck.