When I came of the pill I had my normal pill period and then and then a period 28 days later so completely regular. On that basis I should have started my period Saturday but still haven't - took a test Saturday and it was clearly negative. I've had period type cramps so I was convinced AF was coming and had a few drinks over the holidays here. What I'm asking is - how do you know if you are late and not just out of sync? Thanks!