I doubt you are pregnant with your tubes tied. It 'can' happen but is pretty rare and usually years later from either the clip coming undone if you had them tied by clip or scar tissue forming where they were severed forming a new tube like area if you had the tubes actually cut. Ectopic pregnancy is most common though if pregnancy does occur after tubes being tied which you probably know is not viable and dangerous to the mother. Anyway, you will still menstruate like normal after tubal ligation and will also still have all the oddities that can happen to our cycle like being late. Women are late due to changes in routine, stress, illness, weight gain or loss or just a hormonal fluctuation. So, you are probably just late with some break through spotting. You can always follow up with your doctor to be sure. good luck and wowie, 5 kiddos! You are a busy mama!