You could have a fecal done, but be aware that a fecal would only rule out some pathogens (chytrid
For instance is best diagnosed with pcr). Also fecals do not always come back positive when there is a problem (this is notoriously true for parasites, which is why multiple fecals are typically recommended). I would simply keep the frog in a clean enclosure and monitor things. Keep an eye on its sheds, its activity, etc. Good luck!