Spotting vs Period (a bit TMI)?

Hey ladies, I feel so silly having to ask this, but my body is doing weird things and I don't know how to record it in Glow. I started spotting last Thursday, really really light and that lasted until Saturday (3 days). At first I thought it was IB because it was 8 days before AF was expected, but then on Sunday the spotting got heavier (but still only when I wiped) and on Monday was regular heavy AF. Tuesday was medium and Wednesday was light, and today I'm spotting again. I'm really confused as to how to record this in Glow because I've never spotted before AF before - should I count the first day of spotting as CD1? Or should it be Monday? Thanks in advance if you've read all of this and have some advice!