I have been dx with hyperparathyroidism in the past. That is to say, I was secreteing an abnormal amount of calcium. The symptoms were rather vague, but my most persistant complaint was that I just didn't feel good. Fortunuately, I was seeing an excellent i&d physician at the time and he ran a complete chemistry panel and discovered the high levels of calicium. I then saw an endocrinologist who monitored the calcium levels until it reached 14 and then ordered an mri of my neck. It revealed nothing and so, after months of feeling lousy, I agreed to an explorory surgery of my neck where they discovered a tumor the size of a peach pit that literally popped out with the first incision. They removed it and now I feel fine. Hope this helps.