What could be causing my late period?

Lauren

I track my periods with this app, they are always accurate and on time. Last month was the first month we decided to try for a baby. Well two days ago was supposed to be my period. I have no symptoms either way and still no period. Plus I took a test yesterday afternoon and it was negative.

Can my body just be off because I want to be pregnant and don’t want my period to show up? Or am I crazy?