On September 20th sex,not penatration,no ejaculation,period end on 19th sept, within 12 hrs taken unwanted 72 and on 27th had withdrawal bleeding last for 4 days.in October no period and on 26th November at evening she got bleeding and today 27th the bleeding is heavy.we r very tensed.is that a sign of pregnancy??we tested 3 pregnancy test by kit on 2nd nov,7th nov and 22 nov all 3 r negative.but is this period?why this bleeding is heavy plz help sir/ma'am