First of all google the question online you should find plenty of advice on there. Also give your vet a call and see what he says as it might be nothing to do with that.
Try to keep your pup away from the mould. How much time has he spent in contact with it.Has your pup had all his shote ?? if not get that done ASAP.
Dont wait too long before doing something if he does not improve.But as long as he is eating ok thats the main thing.
i also think he may b allergic to mold n cant cop it
he might have a "poor immune system" n cant fight it .
ask ur vet 4 all these okay
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to mods - sorry for the answer in 3 posts . some things strike in my mind after clicking "post comment" rofl
n free ur home/apartment from mold as soon as possible .it is harmful both to humans n pets
i bet it might have attacked you pup . u giving him love right ...and even if hes aloof .this might b a attack of fungi /mold .
Mold spores can invade you pups lungs !
better off to a vet both of U .