Pregnant but negative urine test?

Mr

Has anyone experienced a BFN but still pregnant? I am three days late and I am ALWAYS on time. My friend was 8 days late and her test never came up positive but she’s now 13 weeks pregnant. Does this really happen!?!? I’m crossing my fingers and am thinking of writing a book called “I hate to pee!!!” Because I really hate to pee right now!