Any moms that had this happned?

has this happnee to amyone. im 4 days late and got a bfn. 3 days b4 af was due i got a vvvvvvvvvvfl on frer. havmt had ANY signs of af showing. been having a couple pregmancy symptoms. took a clear blue yest this morning it was negative. has anyone every been 4 days late and not gotten a possitive but later on found out you were preggers all along