Почему менструация задерживается каждый месяц?

By assuming a standard ovulation cycle of 28 days, ovulation occurs at the time of the next period which is 14 days prior to the period. Thus, your last period began on August 20th, hence you are likely to ovulate on or around September 3rd. Some indications of ovulation are differences in the thickness of cervical mucus, slight abdominal pain, and a rise in basal body temperature. You can also use ovulation predictor kits to check for ovulation.

External hemorrhoids or piles can occur during or after pregnancy due to the increased pressure on the rectal veins and hormonal changes. Hemorrhoids often improve with time and self-care measures such as a high-fiber diet, hydration, and creams. 

It is best to visit a gynecologist who specializes in reproductive health to properly diagnose and treat any potential complications. 

The combination of having sex while using a condom on Jan 16 and then having periods regularly after that indicates that you are not pregnant. Early pregnancy signs can be a missed period, nausea, and breast tenderness. You can also take a pregnancy test yourself for more confidence.