Do not stop praying except in these two conditions!

Narrated ‘Abbaad ibn Tameem from his paternal uncle, that a man complained to the Messenger of Allah (peace and blessings of Allah be upon him) that he imagined that he felt something whilst praying. He said: “Do not stop (praying) unless you hear a sound or notice a smell.” (al-Wudoo’, 134). None of these whispers and thoughts breaks one’s wudoo’.

(He imagined that he felt something) It means he doubts that he passed wind or broke his ablution.