If the amount of bleeding is too scanty to doubt the initiation/completion of abortion, you have to get it confirmed. The best way for confirmation is by ultrasonography which will visually show the images of uterine cavity. If the cavity appears to be absolutely empty, the abortion is complete. However, you should keep in mind the possibility of pregnancy in the tubes which your Obstetrician will investigate if needed and take action. This type of pregnancy when ruptures is associated with little bleeding with severe pain in abdomen. In this the woman bleeds lot more in the abdomen that what is seen outside and needs immediate intervention by surgery and blood transfusion. If the scan shows that abortion is incomplete or the abortion process has not started at all (by evidence of tissues present inside the uterine cavity), then surgical intervention like suction evacuation may be required. Please report to your Obstetrician and get his opinion and help.