What is the ruling regarding the fasting and prayer of a woman who saw pink blood before her usual menstrual period, then it stopped and reappeared, and she continued her fasting and prayer based on the assumption that the blood was not menstrual blood? Does she have to make up the days during which she continued to fast and pray?

The pink discharge, yellowish discharge, and brownish discharge that precede menstruation are considered corrupt blood (dam fasad), not menstrual blood (hayd). Menstruation is recognized by black blood. So, if pink discharge appears, the woman must wash her private parts, perform ablution (wudu') for each prayer, pray, and make up for the days she missed fasting, assuming it was menstruation.