I used to have a diagnosis of "fibromyalgia", on top of a genetic bone disease that I have that put me in a lot of pain, and I was constantly tired all the time. I too didn't know how to start exercising and overcome the initial pain and hell. I eventually hired a personal trainer, to help guide me for a relatively cheap $35/hour, for which he even came to my home. I also drastically overhauled my diet, and added digestive enzymes with every meal(which made a lot of difference with regards to fatigue).
It has been a few years but I went from being on 450mg of Lyrica, 16mg Dilaudid and 75 mcg/h Fentanyl patches(a drug 80 times the strength of morphine), being inactive, weak, always in pain, to taking nothing more than advil, tylenol, voltaren, heat, glutamine, BCCAs, epsom salt baths or doing stretches, foam rolling, self massage, for pain. Strength training has greatly improved my pain and my pain tolerance for that which remains. I also have a lot more energy and am more active these days. I still have severe GI issues that I am dealing with and working on but at least my pain and fatigue are under control. I have several deformities caused by my bone disease, it hurts every time I walk, but the pain is much more manageable.
I would if I were you, workout at home. If you can't afford a trainer, start with basic body weight pilates videos on youtube. Eliminate as many obstacles as you can that are in between you and exercising ie, traveling to a gym. I don't know if the state you are in you are even able to hold a job. If not, and you live at home, just workout at any time in the day where you feel you have the most energy to do so. The digestive enzymes mentioned above take the load off your gut which otherwise requires a lot of energy to digest your food, energy that you can use elsewhere in your day.