Is what came upon her on the sixth day of Dhul-Qi'dah, of seminal fluid, light blood, and abundant discharge, considered menstruation, knowing that it came less than a month after her previous menstruation?

The minimum period of purity between two menstrual cycles is thirteen days, according to the preponderant opinion. If this period or more passes after the cessation of the previous bleeding, then any blood seen thereafter is considered menstruation. As for yellowish or brownish discharge (صفرة وكدرة), it is not considered menstruation unless it occurs during the accustomed period or is continuous with blood. The duration of bleeding must be at least one day and one night to be considered menstruation according to the majority of scholars. Based on this, any blood seen in Shawwal is considered full menstruation as long as its duration does not exceed fifteen days. Any brownish discharge (كدرة) that reappears after that is not considered menstruation unless it occurs during the accustomed period. As for any blood seen after that, if it lasts for one day and one night, it is menstruation; otherwise, it is not.