had sex on saturday (withdrawal: didnt *** inside me), had my period by thursday that last for 5 days (red/brown). i did my 1st PT before the day of my 1st day of period w/ a negative result. 2nd PT on 1st day of my period still got a negative. 3rd PT after the day of period still negative. 4th PT after 2/3days of 3rd PT still negative. 5th PT after 2/3 days of 4th PT got negative. 6th PT after 5/6 days of 5th PT got negative. yesterday morning i had little dark/brown discharge and used my 7th PT got a negative. started to have lower back pain and slight abdominal pain . By evening still have little dark/brown discharge and pain, for the 8th PT got a negative result. dont have any preggy symptoms (no morning sickness, not swollen/tender breast)