Tracking period dates

Renu
What's the correct way of tracking period start and end dates?  If there is some spotting would that count as a period day? For instance, today is shown as a no-period day on my Glow calendar but I'm wondering if I should change today to the last period day because of some light spotting.  Should the first normal day after period be the day of absolutely no spotting of any kind??
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​I feel like I haven't been entering my period days correctly in Glow this whole time...