Serum beta hCG
levels at this stage of pregnancy
should be around 1000 mIU/ml at least and they should double every 48 hours. A fetal heart can be seen in an abdominal sonogram at 7-8 weeks ( since trans-vaginal sonogram is difficult to perform at this stage). Based on these facts and the symptoms that you have, it seems likely that you have an inevitable abortion
. Please consult your doctor for future management. Good luck.