OPK question! Please help me understand😕

Lauren • Expecting baby #1 💙💗 February 2016
Ok, Im on month 9 of TTC our first. This month, my period was 4/15-4/19. First question is do you count the first day of your period as the first day of heavy flow, or do you count the first day when you have ANY sign of AF? For instance; before I start, I always get a brownish red dishcharge. Do I count that as the first day of AF?
Also, on Friday 4/24 I started testing with my ovulation tests. The pictures below (in order) are: Friday afternoon, Saturday morning, and this morning. Shouldn't my test lines be getting darker, not lighter? Idk when to expect to ovulateÂ