Period late but test comes out negative

Hello everyone, I've been trying to conceive for two months or so for baby #3 after 3 consecutive losses. My period is always consistent and always starting on the date expected. I have headaches,fatigue, nausea, sore breast, cramps and lower backache and of course no aunt flow insight. I have tested numerous times with my first morning pee and I keep getting BFN. Has anyone had this happen to them and later found out they were indeed preggers?