Fibromyalgia Support Group
You're not alone in your pain. Fibromyalgia is a condition that can be difficult to diagnose and manage. If you're trying to cope with pain throughout your body, sleep problems, general fatigue, or other common fibromyalgia symptoms, you're in the right place. The community is here for you to talk about therapies and share your challenges.

If you have not had a sleep study done, that is something that you should consider. Managing the sleep issues that accompany Fibromyalgia is critical.
Do you take medication before bedtime to help with sleep ? Elavil (Amitriptyline) before bedtime is one of the drugs commonly prescribed to help with sleep and pain. Unfortunately, patients build up a tolerance and the dosage has to be increased the longer you take it. You probably need to talk to your doctor about a medication to help you sleep
The best treatment is nutrition and rest, in my personal experience of it. Get those levels checked. A little Iron with B vitamins can do a lot even if you eat very healthy ----- sometimes, our bodies don't absorb as swell when we're "down", as I was.
The main distinction seems to be this: Is fatigue the main symptom or pain? If fatigue, then they'll go for CFS. If pain, then fibro. Yeah, I know, not exactly a brilliant distinction to use, but it's what they use.
This pamphlet from Cleveland Clinic offers a (somewhat trite) but useful overview. https://health.clevelandclinic.org/are-you-always-tired-and-achy/