Symptom: You feel a twinge, and you're sure it's nothing (pretty sure, anyway).
Causes: Between 86 and 95 percent of people report a physical symptom (headache, back pain, a rash, a bump) in any two-week period, says Kelli Harding, MD, a psychiatrist at New York-Presbyterian/Columbia. Most of the time, these aren't serious and are attributable to ordinary hassles such as stress, poor diet and a lack of sleep or exercise. But when some rare case turns out to be life threatening, we all hear about it in detail from the news or from our social network. Adding to our encyclopedic knowledge of the ways the body can betray us (thanks, Internet) are the pharmaceutical commercials with their long lists of potential side effects.
Treatment: It can be hard to accept that being healthy doesn't necessarily mean being symptom-free, says Harding. If you aren't satisfied with your doctor's diagnosis (even if he went to the best med school in the country), Harding suggests getting a second opinion—from the same doctor. It forces him to rethink the situation and also gives you a chance to examine his rationale. Try something like "Can you walk me through how you ruled out that it's not a brain tumor?" If the bump persists and the anxiety remains, get a third opinion, this time from another specialist. (By the way, the chance that you'll develop a malignant brain tumor in your lifetime is less than 1 percent.)