This is a disorder in which people mistakenly fear that minor changes in their physical functioning indicate a serious disease. somatic symptom disorder munchausen syndrome illness anxiety disorder munchausen syndrome by proxy

Answer;

illness anxiety disorder

Explanation; illness anxiety disorder sometimes known as hypochondriasis, is a disorder in which people strongly believe they have a serious or life-threatening illness despite having no, or only mild, symptoms. The symptoms of illness anxiety disorder include; Excessive worry over having or getting a serious illness, physical symptoms are not present or if present, only mild, fear of illness which is normally not due to another mental disorder and excessive health-related behaviors.