What should a person who has waswasa (extreme anxiety or misgivings) while performing ghusl and minor ablution do?
Waswasa is the state of quandary, doubt, and delusion faced by people due to various reasons. It generally occurs as obsessive doubts of a person on whether or not he performed ablution and ghusl, whether he has performed it properly and completely or not, or if they are nullified or not. A person who performs ghusl or ablution does not need to repeat his ghusl or ablution due to waswasa. Besides, one should not give credit to such waswasa (Ibn Majah, Taharah, 48), tell himself that this condition of doubt and quandary is baseless, and if needed, he should consult to a doctor for psychological treatment. Also, as spiritual support, he should recite chapters of al-Falaq and Nas by pondering over their meanings, and pray to Allah to be saved from this condition.
Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS