Is what comes down after seeing the white discharge considered menstruation, or is it to be disregarded due to the presence of the sign of purity?

If a menstruating woman sees the white discharge, she has become pure, based on the statement of the Mother of Believers, Aisha: "Do not hasten until you see the white discharge." Anything that comes after that, whether it be turbid discharge or yellowish discharge, is not considered anything, based on the statement of Umm Atiyyah, may Allah be pleased with her: "We used not to consider the yellowish and turbid discharge after purification as anything."

However, if blood comes down, there is a detailed explanation: 1. If it is a few drops, it is not considered anything, because menstruation is flowing blood, not drops, especially after the completion of the cycle. 2. If it is flowing blood, then it is menstruation, so you should refrain from prayer until you become pure, unless the blood exceeds fifteen days from the first appearance of your menses. If it exceeds fifteen days, then you are experiencing abnormal uterine bleeding (istihada), so you should perform ghusl and pray. You should sit out the duration of your usual period if it is regular, then perform ghusl and pray, and you must perform ablution for each obligatory prayer after its time has begun, based on the statement of the Prophet, may Allah's peace and blessings be upon him, to Fatimah bint Abi Hubaysh: "No, that is from a blood vessel. But leave prayer for the number of days you used to menstruate, then perform ghusl and pray." If you do not have a regular period, you should act according to distinguishing characteristics. If the blood has the characteristics of known menstrual blood, then it is menstruation; otherwise, it is abnormal uterine bleeding. If you do not have a regular period, and you cannot distinguish the blood by its characteristics, you should sit out the predominant duration of menstruation, which is six or seven days, according to the custom of the women in your family.