You are thinking of "Malingering" . This is intentionally faking illness in order to gain some perceived benefit, like getting out of some kind of work or duty. A malingerer will go so far as to exaggerate or even produce symptoms in order to appear ill. You might have had "Hypochondriasis" in mind, but Hypochondriasis is the fear of being ill, even though there are no symptoms. This may be more than you wanted to know, but there is another related disorder called "Factitious Disorder" where a person will fake the sick role, as in malingering, but there is no external incentive. The reasons for this disorder are more psychological in nature, rather than to gain some real benefit. There is more in the Diagnostic and Statistical Manual of Mental Disorders, if you want to do a little digging.
If you are talking about the feeling like you want to throw up, the term is nausea.
Hypochondriasis is the medical term meaning condition of always thinking you're sick. Sometimes the word somaticization is used to mean attributing medical symptoms to conditions that are not related to the body (soma) but are related to psychosocial issues.
Anacusis is the medical term meaning complete deafness.
Syncope is the medical term meaning fainting.
Lamina is the medical term meaning layers.
Sensation is the medical term meaning feeling.
Eructation is the medical term meaning burping.eructation
Atrophy is the medical term meaning shrinking.
Metastasize is the medical term meaning "to spread."
Stasis is the medical term meaning stopping.
Strabismus is the medical term meaning cockeye.
Kyphotic is the medical term meaning humpbacked.