This is the Wikipedia page for Ehlers Danlos Syndrome. it explains the main six types. I have the hypermobile type. Hypermobility aka being double jointed is not a symptom of fibromyalgia. I've been super bendy my whole life. I could see the fibro when they diagnosed me with it, but I knew something else was going on. I have a lot of random joint dislocations and subluxations (partial dislocations) and have had those my whole life, especially my knees going out and knocking me to the floor. (not a fibro symptom) Since I've always done that, I didn't know it was abnormal. The last few years though, these symptoms and more have gotten worse.
http://en.wikipedia.org/wiki/Ehlers%E2%80%93Danlos_syndrome
I know people with the classical type and the vascular type but I definitely have hypermobile EDS. They used to call it type III. EDS is a genetic connective tissue disorder (it's a dominant gene but can happen randomly in a family with no history of it). It causes the body to make weak collagen which is everywhere. It's the substance our bodies use as "glue" to hold tissues together. Swallowing problems are common among EDSers but lots of other things are too. I have severe pain too. It's pretty much everywhere and down to the bone, like you described. I inherited EDS from my Dad who passed without knowing he had it. He'd had emphysema since I was little which one of my doctors said was likely made worse by weak tissue around the lungs. There is collagen in the fascia around the lungs. I have allergic asthma caused by the same kind of weak tissue. My skin is very soft and doughy, so about the only good symptom I have is that I look tons younger than I am.
This is another site that has a lot of info
https://www.edsers.com/
EDS doesn't show up in bloodwork as they're not testing collagen when they take blood. Early osteoarthrtis is another sign I have. It's in both knees, my right shoulder and my lower back. There is no cartilage in my right knee at all. I have fibro too but my Dr said mine was caused by the EDS. I was a "floppy baby" with low muscle tone. It took a long time for me to learn to walk. My handwriting is terrible but that's because my fingers are hypermobile. I can give you my yahoo IM but my facebook page is waterswaves if you want to ask me any direct questions. I'll put the link here to the Ben's Friends EDS group too. It's a newer group but as more people join more info is shared.
There are studies being done about EDS now. A geneticist is usually the one who diagnoses it. Most doctors know little about EDS so it gets missed a lot. There are a few specialists, Dr Tinkle in Chicago, Dr Francomano in Baltimore and Dr Levallee in Indiana. They have very long waiting lists and I couldn't travel to them, so I went to the University of Michigan for diagnosis. There are so many symptoms of EDS that it's hard to list them all. I made a checklist and wrote up a medical history of all possibly related conditions and symptoms when I went for diagnoses. it seemed to help a lot. I'm lucky in that I pointed out a few symptoms to my rheumatologist and she knew enough about EDS to refer me to U of M. She wanted to know why I hadn't shown her before but they were mostly issues I'd had my whole life.
http://www.ehlersdanlossyndromesupport.org/
Other things that happen with EDS a lot are, gastroparesis (the stomach and digestive system move too slowly causing other issues), IBS, GERD, livedo reticularis (I have this, its a lacy pattern on the skin that's caused by blood vessels not restricting correctly) joints that pop, snap, and crack a lot more than they should, severe pain, chiari malformation (this can cause headaches) thin skin, skin that tears easy, arthritis, fatigue, weakness, and more. Mast cell issues seem to happen a lot in EDSers too. Part of the problem is many people suffer from different combinations and severity of symptoms which makes it harder to diagnose. We don't fit in a "box". Some symptoms can crossover between types too. I hope I'm not scaring anybody but this gets missed a lot. Hugs to all that need one and feel free to friend me here or on facebook.
Susan W aka water