Must I repeat the Witr prayer if I had a misgiving that I prayed four Rak'ahs instead of two, then the Witr?

If there is doubt about the Shaf' prayer, whether one or two rak'ahs were performed, then it should be considered one rak'ah, and another rak'ah should be prayed. The prostration of forgetfulness (sujud al-sahw) should be performed before the taslim (salutation), and then the Witr prayer should be performed. No attention should be paid to the obsessive doubt that the Shaf' and Witr prayers were three rak'ahs, because this obsessive doubt contradicts acting upon what is presumed correct, due to the Prophet's (peace and blessings be upon him) saying: "If one of you doubts in his prayer and does not know whether he prayed three or four (rak'ahs), he should cast aside the doubt and base (his prayer) on what he is certain of, then prostrate twice before giving the salutation."