I recently took a pregnancy test that resulted in a positive test. I took one last week and it was negative. I am trying to remember my last menstrual period, but I can't remember. All I remember is having it three times in the month of August. I want to calculate my due date, but am at a loss with my memory and hormonal fluctuation. I usually had my period towards the end of the month, that is why I took the test. How early does the home pregnancy detect the pregnancy hormone, 4 or 5 weeks????