نواقض الوضوء

Wudu is broken by what comes out of the private parts (urine, stool, wind), by deep sleep, and by losing consciousness. These are the points everyone agrees on. Other things, such as touching the private part, bleeding or eating certain meats, are discussed differently between the schools.

If you doubt whether you broke your wudu, you stay on what you were sure of. The Prophet ﷺ taught not to leave the prayer unless you hear a sound or find a smell (Bukhari 137, Muslim 361): the doubt alone changes nothing.

Schools of law differ on some details: follow your family's and mosque's school, and ask a teacher.