you're doing the right thing by bathing it, sometimes they do get a bit stuck. However it is something to keep an eye on and if it doesn't look to be improving after a couple of days a vet check - as of course if the kitten starts sneezing or goes off its food, loses weight etc. With kittens her,e after the bad experiences we have had, its if in doubt - get too vet.
I don't know how much your vet charges and hopefully they will have a limited surgery tomorrow. At the end of the day I'd rather pay £30 for a 'wasted' visit than have an ill kitten or a worried fosterer plus the fact it is never really wasted as you always improve as a fosterer from a visit to the vet.