you count day one as the first time you start bleeding...the last day is too hard to pinpoint because of spotting occurs after you have in actuality stopped. Usually a cycle is 3-7 days depending on...
I thought you start the count the FIRST day you start bleeding...and count 28 days, this should be your next "cycle" and so on.
Though some girls are earlier or later than others depending on...
If by "not safe" do you mean most vulnerable to get pregnant, then that would during the ovulatory phase of your menstrual cycle. But any day of your menstrual cycle or any other day is "not safe" if...