People with health anxiety have a preoccupation with the belief that they have or will soon develop a serious illness. If you tend to become overly preoccupied with worry about your health, and avoid situations which might triggering your anxiety, then you may be suffering from health anxiety.
People with health anxiety will misinterpret normal bodily sensations, such as a headache, to mean that there is something seriously wrong. Similarly, they may hear about someone falling ill and then begin to scan their bodies for signs of similar illness, which often results in their finding some evidence to make them believe they will be getting sick soon.