You’re not clean, though. You’re really, really not. You’re cleaner, but humans are disgusting and a residential shower is in no way getting you anything close to actually ‘clean’. You don’t have to be insane like I am and swap them out every shower, all the literature I can find says 1-3 days is probably fine, but please please get a couple more towels and swap out for a clean one every few days at least, right now you’re just culturing some very nasty bacteria and then rubbing it all over yourself.
Oh my god, that smell is mildew. If your towels are kept so humid that they’re mildewing the colliform bacteria in your bathroom is having an entire festival on there. Please, before you get a horrible infection, please start swapping them out more frequently. I’m begging you, rubbing that on even a small open wound could be legitimately life threatening (for example if you’re the lucky winner of E.Coli roulette, which is also absolutely growing on your towels).