Implantation bleeding/spotting?

I didn't track my ovulation this month, but according to the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> prediction, I'd be 7dpo today.

Could this be implantation bleeding / spotting? Was light pink and some was light brown.. Was only there when wiping, none on panty liner.