About 4 years ago I started to get a small red area under the skin on my upper arm. Over time it grew to a quarter size spot and now I have several more on my upper arms, a couple on my upper chests and one is now appearing on my neck. They do not hurt, itch, or bother me in any way. They also get darker when I take a bath or get hot. I have also experienced poor health in these years, with periods of fatigue, no energy, slowed mental capabilities, weakness in extremities, general soreness (even to the touch) over the entire body. Do you have any idea what could be the cause?