No Period/Neg Test ...Help?

Gaby

So it seems I am late with my period. I took two test and both came negative Monday and Tuesday of this week. I was suppose to get my cycle on the 25th and now the 4th and no period. I recently took a plan B pill a week and half ago. Can this delay my period or give false negative test? I do have a Dr. appointment sometime this month. I have attached my log maybe someone can help me, maybe I am missing something? Remember I did not get my cycle.