had sex on last day of period on February 28th and took plan b on February 29th had sex again on March 3rd but both times he didn't cum my ovulation day is March 8th at the earliest and that would of been 6 days after  and I never ovulated but I bled lightly one day on March 10th which was 10 days after taking the plan b pill is that normal could it be from the plan b pill. I don't think I would be pregnant because we had sex 6 days before ovulation that never occurred please help