A 2-day delay in getting your menstrual flow could be considered a normal cycle variation. A late period can be due to many reasons but the first thing most doctors assume is that it is caused by pregnancy. Pregnancy can be easily confirmed or excluded by taking a home pregnancy test.
Stress can also cause a period delay. That is because the nerve centers that control the emotions and those that control the endocrine functions in the brain are close together and somehow connected.
The presence of a hormonally active (functional) ovarian cyst can also cause period delay.