I have missed my periods in the month of may. My expected date was 25 may, based on the previous month cycle. But I haven't got my periods till now. I had last intercourse with my partner in the first week of april but after that on 24 april I got my periods. However, in the month of may, I got my first dose of vaccine for covid on 7 may. And I was fasting due to the Ramadan till 12 may. Can it be a reason for the delay? Its been 12 days of delay form the expected date.