A good internist could probably rule out the most obvious serios conditions. If you read this page, you may see your symptoms lining up.

http://www.flcv.com/cfsfm.html

You will also get some ideas of supplements to take. In all probability, you either have a parasite infection(many here have had one) and or mercury or other heavy metal toxicity(lead is also a big problem), and/or nutritional deficiencies. When I first become ill years ago I went to over 20 doctors, and none of them were of much help. Some insulted me and told me I wasn't really sick, while others believed I was sick, but didn't have a good treatment plan. Lately I have been devising my own treatment plan. Over time I am becoming more knowledgeable.