13 dpo implantation bleeding? Unlikely right?

So I only got BFNs so far. Yesterday I woke up with some light pink spotting at 13 dpo (if my app was right that is...it could be 12 dpo if I ovulated later) when AF was expected at 14 DPO (today). Just assumed it was my period, was sad but ready to move on. Well...36 hours later, that was the only bleeding I’ve had. Just that light pinkish spotting. Usually day 2 of my period is super heavy...and I literally haven’t had anything. Just a little CM. There’s no way that was implantation bleeding, right?? My period is just being a little b*tch this month, right? Lol. I have had two pregnancies and neither had IB. First I got my BFP at 15 DPO, and second I got it at 13 dpo. Unlikely right? It’s too late and wouldn’t I have a BFP by now? Ugh I hate AF when she decides to be a tricky monster.