Does ritual impurity transfer to swimming trunks placed over underwear containing prostatic fluid (madhiy) or vaginal discharge? And is the water remaining on the hands or clothes after washing away prostatic fluid (madhiy) considered pure or impure?

It is advised to ignore whisperings (waswas) and not pay attention to them, for impurity does not transfer merely by doubt. If you doubt its transfer from one place to another, its transfer is not confirmed except by absolute certainty. If the transfer of impurity to clothes is not certain, the default is their purity. Water that separates after purifying an impurity is judged to be pure if it has not changed due to the impurity.