5days late and negative test results

Not sure if anyone has had this same issue before. I am five days late. A few nights ago had intense cramping like never before. Period has still not come. Having feelings of slight nausea and headaches. Discharge is watery. Usually thick and creamy when period is about to start. I have never been this late before and my boobs only just started feeling tender last night. Have taken four tests and all negative. I have been told it could just be too early for my body to pickup the pregnancy hormones.  Pregnant or not that is the question 😕