Is it valid to perform ghusl after seeing a brownish discharge (kudrah) followed by a white discharge (al-qassah al-bayda’), and then pray without observing the correct order between Maghrib and Isha due to obsessive doubts (waswas), and then only repeat Maghrib?

If a woman experiences purity, indicated by one of its two signs, she must perform ghusl (definition) (ritual bath). If she observes dryness during her menstruation, she may wait a day and a half, because it is common for blood to intermit and flow. As for combining two prayers, scholars have differed on this matter, and the opinion that it is not obligatory is strong. There is nothing wrong with your action as long as it aligns with this school of thought. We advise you to treat obsessive thoughts and get rid of them by ignoring them.