Understanding Your Cycle: LMP and Ovulation Tracking

Question
Hello Dr. Rappaport. I am 30 years old, with no children but my husband and I have been trying to conceive since May.  My question is actually about the date of my LMP.  I started my period yesterday.  However, I had spotting once on Thursday.  Then again Friday evening(more then on Thurs).  Then I started yesterday with the "real" thing (heavy bleeding and major cramps).  So to help me with tracking my cycle and ovulation, should I consider Thursday cycle day 1?  Or Friday?  Or yesterday?  

Thank you so much for your time and help on this!

Answer
You have to consider the first day of your bleeding (either spotting or staining or bleeding) as the first day of your period (Cycle day #1). If you have a regular 28 day cycle (from the first day of your period until the first day of your next period) ovulation occurs on cycle day #14 and you can become pregnant if you have sex on cycle day #13, 14, 15, or 16.