What is the ruling on the fasting and prayer of a woman who saw brown discharge then red blood after her menstruation ceased due to birth control pills?

The minimum duration of menstruation is one day and one night, and its maximum is fifteen days and nights according to the majority of scholars. The minimum period of purity between two menstrual cycles is thirteen days and nights according to the Hanbalis, and fifteen days and nights according to the majority of scholars. There is no maximum limit for the period of purity. If a woman sees blood at a time when it is valid to be menstruation (not exceeding 15 days, and there are 15 days or more between its appearance and the cessation of the previous bleeding), then it is menstrual blood. She should refrain from fasting and praying during this time and perform ghusl (ritual bath) after its cessation. If the bleeding exceeds 15 days, then it is Istihadah (non-menstrual bleeding). In this case, ghusl is required after the menstrual period, and ablution (wudu) is required for each prayer after its time has begun. The prayers missed during the period of Istihadah must be made up. The last blood is considered menstruation as long as it is valid to be menstruation and has not exceeded the maximum duration of menstruation. Brownish discharges (kudrah) are not considered menstruation unless they occur during the habitual period or are connected to blood.