What is required of her now, and must she repeat the prayers, knowing that she did not wait for the cessation of the pink discharge after menstruation and performed ghusl immediately, and she is assailed by the whisper that she prayed without being in a state of purity?

The pink color is one of the colors of blood, so it is not permissible to perform ghusl before verifying the cessation of menstruation by one of its two signs: dryness (al-jufūf) or the white discharge (al-qaṣṣah al-bayḍāʾ). The doctor's statement about the duration of menstruation is incorrect. As for making up the prayers that were performed without ghusl, there is a difference of opinion among scholars regarding it. It is permissible to adopt the view of those who do not see it obligatory for someone suffering from waswasah (obsessive whispering) to make up the prayers. One must hasten to perform ghusl.