So last month glow was right on the date with my period. Usually when it's a day before I start if we have sex It will make me start and I had sex last month on December 13 th the day glow told me I was gonna have my period we had sex then started my period right after. Well this month I was suppose to start on jan 3rd we had sex and still no period so when should take a test?? Should I wait a few more days or weeks?