Is the blood that comes five days after the end of the second menstruation considered menstruation, knowing that the previous menstruation stopped for nine months due to breastfeeding, and how are the days calculated to determine that?

If the blood a woman sees does not exceed fifteen days, then all of it is menses. If it returns to her after five days, it is menses. However, if the total number of days of bleeding and purity exceeds fifteen days, the woman becomes a mustahadah (experiencing irregular vaginal bleeding), and in this case, she considers her previous habit as menses, and anything beyond that is istihada (irregular bleeding). But if the returning blood stops before exceeding that period, it is menses. It is also menses if the period separating it from the previous blood is less than the minimum period of purity, which is thirteen days according to the Hanbalis, and fifteen days according to the majority of scholars.