AF came Jan. 20-25 on a 24 day cycle. 4 days before I was supposed to start I took a test on a whim and got multiple positives, I couldn't be happier! As of now I'm only 2 days late on my period. Your not supposed to show a positive until it has implanted in your uterus and your body starts producing HCG. Therefore, IT DOESNT ADD UP! The previous period was on December 21st and regular. By going off my last period Im afraid when I finally can get my ultra sound I'm gunna be futher along. Any input is appreciated!