Should I be concerned by a musty smell after cleaning the shower with bleach?
open the little crate covering the drain. it's usually a small twist left and lift up. using a bottle brush or similar implement give the drain and the crate a good scrub, removing all the mess of caught hair. it's a bit mucky but should provide a cleaner smelling drain. not that it's ever going to smell like roses. bleach turns to gas a bit and will bring up the smells from the S bend. the water that stays in the S bend stops smells coming up from the rest of the pipe.
i finally got my wife off bleach. it smells bad, isn't that good to breathe in and bleached lots of good clothes by accidents.
we now use cream cleaner for shower cleaning, which cleans scum off much better.