I so understand your frustration. I have an inner ear disorder that causes vertigo and balance problems. It took me about a year to get diagnosed, with a couple of "specialists" telling me that it was just anxiety.
Well, lets see... If the room is spinning, you feel like you are falling in a hole, and you can't stand up straight - YES, you are going to have anxiety!
I know that both depression and anxiety can cause pain and fatigue, but they are also very often symptoms of other illnesses. Often, when the primary illness is treated, the depression and anxiety will lessen. Of course, sometimes treating the anxiety/depression is just part of the total package of illness management.
Hope you get some relief soon.
BTW - The Doogie Howser comment is just too funny.
"There is no charm equal to tenderness of heart." - Jane Austen
Fibromyalgia, 2 back surgeries, Meniere's Disease, 30+ kidney stones, GERD, IBS, Asthma, Allergies, Endometriosis, Heart Arrythmia, Myofascial Pain, TMJ.