When is my period truly over?

I feel so silly asking this, but sometimes I don't know when my period is officially over. The pattern is like this. CD1:light bleeding CD2:heavy bleeding CD3:medium bleeding CD4:light bleeding CD5:spotting that doesn't require me to change my pad (I do anyway for bacterial reasons) CD6: barely anything just when I wipe only get a tiny bit of blood. I'm wondering if I should mark my calendar that my period ends on CD5 instead of 6. Also I'm new to this app and I've seen some users calendars have their predicted ovulation day marked in purple....I don't seem to have that on mine. How can I make it show up in purple. And should I only have sex on the green days? Thanks a bunch ladies :)