What should I do if I purify myself and pray, thinking that the white discharge (al-qassah al-bayḍāʾ) has appeared, then discover that it has not yet appeared?

If a woman performs ghusl before seeing one of the two signs of purity (the white discharge or dryness), and then discovers she has not yet become pure, she must wait until she sees the white discharge or dryness. She should not pray or fast during that period. Then, she should perform ghusl again, because the first ghusl was not valid.