Ok what is happening

Spencer • 26, dental hygienist, trying for baby #1

I'm typically very regular in my cycle. AF was due the 26th. Today is the 29th and still no bleeding. I've been cramping this whole time like I've been on my period. Realll cramps. And a sharp pinch on my right side uterine region yesterday. Diarrhea on and off the past 2 days but I don't feel sick. Very slight breast tenderness but I took a pregnancy test yesterday mid day and 1 today with first morning urine. Both negative. Wtf is happening.