Is the prayer of one who smells the odor of a passing of wind during his prayer, yet does not feel anything निकल, while being certain of being afflicted with whisperings (waswas), valid, or must it be repeated?

Your prayer is valid, and do not pay attention to any smell you perceive as long as you have not felt anything exiting from you. Do not mind the whispers and doubts, for certainty is not removed by doubt. The Prophet, peace and blessings be upon him, was asked about a man who perceives something during prayer, should he interrupt it? He said: "(No, not unless he hears a sound or perceives an odor)." This hadith is for one who perceives something and doubts its exit, and it contains a prohibition against acting upon whispers. Satan is eager to corrupt deeds, so beware of his plots and do not pay attention to his whispers. Assume a state of purity, and do not repeat ablution unless you are certain, with full conviction, that something has exited.