Abnormal period... Why?

💙Shadoe✨ • Just conceived our rainbow baby:) M/C in March 14 & chemical November 14... Going to marry the man of my dreams<3 After 14 months of trying finally got our BFP 8/7/15! Praying for a sticky baby🚼
A normal period for me is heavy from day 1-4, then medium on day 5 and that's It. This month tho is different. I started 4 days early with some very light spotting. Day 1 continued with spotting. Day 2 very light flow. Day 3 spotting again... Light enough that wearing a panty liner was enough. Day 4 is spotting still... I have been off of depo for 11 months now with a chemical pregnancy in November. Took a pregnancy test today an it was negative.... What would cause me to have such a light period? Any thoughts ladies?(learn more on Glow: https://glowing.com)