Does the bedding, covers, and touching of other things become impure in the event of feeling pre-seminal fluid exit, then it dries without seeing any trace of it, and then touching the underwear and then other things?

"Madhy" (pre-seminal fluid) is a viscous, impure fluid. Its location on the body and clothes must be purified if its emission is confirmed. A strong presumption is sufficient for removing the impurity, to avoid hardship. However, doubt about whether clothes or other objects have been afflicted by madhy does not necessitate washing them, because the default state is purity. One should beware of obsessive doubts (waswasa).