I’m not stressing, so what else could be going on???

I’m 10 days late and all my test coming back negative. I am TTC as I did have sex with my SO during my ovulating window last month. I’ve never been this late, and having period/pregnancy symptoms like, mild cramps, fatigue, and nausea the most. I’m waiting for my doctor to come back in town as then I will be making an appointment. It’s very frustrating to not know what’s going on. I just don’t believe to be pregnant with a negative result. My last two pregnancies came up positive right away.