How can a woman know that she has become pure from menstruation, and is dryness a sign of purity, and for how long does it last? What is the color of the white discharge (al-qassah al-bayda’)? And does she have to make up the prayers and fasts that she performed based on a mistaken sign of purity (brown discharge)?

A woman identifies purity by one of two signs: dryness (the cotton swab comes out clean) or the white discharge (a thin, white fluid). Yellowish and brownish discharges connected to blood are considered menstruation.

Your ghusl (ritual bath) before the cessation of the yellowish and brownish discharges connected to blood was not valid.

Scholars differ regarding making up prayers and fasts performed before complete purity. Some do not obligate the ignorant to make them up, while the majority obligate it, and this is more cautious.

If you wish to make them up but are unable to determine the number of prayers, then estimate the number that you most likely believe will clear your conscience.