To get rid of carpet mold, start by sprinkling baking soda over the mold and leaving it on overnight, which will absorb moisture and bad odors. Then, vacuum up the baking soda and scrub the mold with white vinegar to kill it. When you're finished, blow dry the areas you scrubbed so they're not damp.
I hate to be the bearer of bad news but it really needs to be checked out...alot of molds are toxic to humans and pets and mostt likely the carpet will need to be removed because mold usually wont just stay on top its most likely underneath the carpet also.
its probably growing from underneath and up, the tip of the iceberg as one might say. otherwise, oil of cloves is meant to get rid of mould.