Thanks for your query,
If the ultrasound
shows no heartbeat even at 6 weeks then it may be a case of blighted ovum
. For its confirmation repeat ultrasound is done after one week. Duphaston is a progesterone
given for sustaining pregnancy and is of little help. It seems you are suffering from threatened abortion
which may progress to abortion if bleeding increases. You should be on bed rest and take the medicines as suggested. This is what you can do at this stage.
Take care and good luck
Hope it helps you..