What is the ruling concerning the Hajj of a woman from whom a slight yellowish discharge (kudrah) was emitted after the tawaf of arrival (tawaf al-qudum) and then stopped, then it reappeared after the tawaf of Ifadah and stopped upon her return, then two drops of red blood appeared on the first day thereafter, whereupon she became pure and prayed for five days, then her regular menstruation began at its usual time after she had stopped taking birth control pills?

If the brownish discharge appears outside the time of menstruation and is not followed by blood, it is not considered menstruation, and your circumambulation (tawaf) is valid. As for the two drops of blood, if they can be considered menstruation within a period not exceeding fifteen days (including any subsequent blood and intervening purity), then they are menstruation; otherwise, they are not. If they are considered menstruation, then you should have performed ghusl (ritual bath) after their cessation. It is safer to make up the prayers of those days if you did not perform ghusl.