Is the appearance of red threads or discharge when washing the sensitive area after the apparent dryness of the sanitary pad considered a continuation of menstruation or not?

What is considered the sign of purity (tuhur) is inserting a piece of cotton into the private part, and it emerges clean, with no trace of blood, yellowish discharge (ṣufrah), or brownish discharge (kudrah) on it. If a woman sees this sign of purity, she should promptly perform ghusl (ritual bath). If she then sees blood after that, she is considered to be menstruating again and should perform ghusl after it stops. However, yellowish and brownish discharges after purity are not considered menstruation.