Hi. I know you think you KNOW when you ovulated but I can tell you that the body really doesn't always let us know. :>) Women are late all the time and it is nothing to worry about. Even regular gals are late from time to time. Things that make a period late--- stress, changes in routine, illness, vacation, holidays, weight gain or loss, more frequent exercise, nothing at all, hormones just fluctuate. Nothing to worry about. good luck