It is very common to feel a bit anxious when your cycle doesn't go exactly as expected. Typically, Duphaston (dydrogesterone) is prescribed for 3 to 6 cycles to help regulate periods. After finishing a treatment cycle, your period should start within 3 to 10 days. A slight delay after your second cycle can be normal as your body adjusts to the hormone. However, since a delay can also indicate pregnancy, I gently suggest taking a home pregnancy test. If it is negative and your period is delayed by more than two weeks, please consult your doctor to discuss your next steps.