Lucy is convinced she smells rotten eggs, but no one in the house can smell the odor. lucy's sensation is known as phantom:

Lucy's sensation is known as phantom "smells."

Phantosmia is the medical word utilized by doctors when a man smells something that isn't entirely.  

Phantosmia is additionally called a Phantom smell. The scents change from individual to individual yet are typically upsetting, for example, consumed toast, metallic, or compound scents.  

Issues with the nose, for example, sinusitis, or states of the sensory system or mind, including headache, stroke, or schizophrenia can cause phantosmia.

a is the final ! : )