5 days late??

This app says im 5 days late. GLOW says I'm 4 days late and My Day says I'm 2 days late? I've taken 4 tests now some in the morning and some in the afternoon and all negative. No faint lines whatso ever. What to do? Wait it out? I'm just tired of going into the clinic and wasting $100 just to get my negative test with blood work.