Faint lines estimated 5 wks 2 days

Last AF was May 11th I’m suppose to be 5 wks but the embryo should only be about 4 wks is it normal to have a faint positive in this early stage of pregnancy no cramping no bleeding no back pain my period is official missed by 6 days my Af only lasts 5 days I’m just nervous because everyone else has bright positives and I have faint lines should I be concerned?