Has anyone gotten a BFN day of missed period....

Stacey • Angel baby 2/3/18 😇 rainbow baby born 12/18/20 🌈 and baby #2 due 11/8/22

And still ended up pregnant? Today was my period day and usually glow is spot on with my due dates but I tested negative (I'm pretty sure, pics below) but I've been cramping on my right side for 2 days now and I've also been super light headed the last couple of days. Not sure what is going on