Myofascitis (muscle fiber inflammation): a condition where muscle fibers are inflamed. This can be either acute (a specific injury or infection of a muscle) or chronic. The chronic condition is much like Fibromyalgia. Your muscle fibers are tender or inflamed and just hurt.
Myofascial Pain Syndrome (pain syndrome of the muscle fibers): This condition is characterized by tender points or trigger points in various muscles that when pressed on are very tender and can refer or radiate pain themselves. Some experts believe that Myofascial Pain Syndrome can turn into Fibromyalgia.
Fibromyalgia (fibers of the muscles hurt): is a chronic condition where you have pain in a variety of places throughout your body, especially in your muscles, ligaments, and tendons; as well as, fatigue and multiple “tender points” or “trigger points”. The pain can be vague (more aching than sharp) and can change intensity from day to day. Most people with Fibromyalgia also suffer from fatigue and sleep disturbances.