BFN ON DAY OF EXPECTED PERIOD?

Hello, my period is due today. Couple days ago I had slight cramps. Cm was watery yesterday only today I have no discharge. No cramps either. I tested and got a BFN. Has anyone got a BFN on the day period was due then got a BFP after? Am I out since I got a BFN ? 💔 also about a week ago I bled for one day only which is weird.