Yes, you need a vet ASAP! Or at least get that poop tested asap! I have a suspicion that frog was WC and was never treated. It has to be done asap. A tank completely disinfected.
get it to the vet ASAP, meanwhile place a frog in quarantine rank, wet papertowels, some easily disinfected decor. Everything has to be completely disinfected, papertowels changed every day until your vet will give you ok to do otherwise.