12 days late

Sh

My period was 12 days late. All pregnancy tests came back with BFNs. I stopped testing around 3 days ago. Yesterday I “started” but it is SUPER light and it’s brown /light pink. I don’t even have to wear a tampon or panty liner. I only see something when I wipe. What in the world is going on? I’m usually super heavy and require ultra tampons. Anyone had this happen before?