What Causes A Red Circle Around The Dry Skin On The Abdomen?

Hi I have recently found a dime size circle on my upper stomach that is red on the outside of it and has a little dry skin on the inside of it, i have had it for about a month now and tonight found two very much smaller similar red circle on each of my hip. They dont itch, but they seem to get bigger when I take a hot shower, What could it be?