Why this site does not include a period calendar.
Period tracking can be useful for some people, but it is not the purpose of this site. This content is designed as an information node: you can read about product types, product instructions and support routes without entering dates, flow notes, symptoms, age, or personal history.
If your question is about new bleeding between periods, bleeding after sex or bleeding after menopause, the NHS says this should be discussed with a doctor. This site does not diagnose symptoms or replace professional care.