What is the ruling on the purity of my ritual bathing this month and throughout the past years, given that I used to perform ghusl on the seventh day after seeing the black discharge, and this month I performed ghusl after seeing the white discharge that had some light brown color mixed with yellowishness?

A woman becomes pure from menstruation upon seeing the white discharge or complete dryness. Performing ghusl (definition) (ritual bath) while black blood is still flowing is not valid, and the prayers offered with such a ghusl are not valid due to the absence of the condition of purity. These prayers do not need to be made up, because the Prophet, peace and blessings be upon him, did not command those who erred in their prayer or the woman with istihada (prolonged non-menstrual vaginal bleeding) to make them up.