Adobe Photoshop Elements 5.0 Paintbrush Problem?

The brush somehow probably got set for additional colors to be picked at random. In the Options bar there is an icon for setting on how the brush behaves. It is the icon titled More Options. Perhaps the Hue Jitter is set for something other than zero. Problem with Color Replacement ---- look in the dialog window for Replace Color to see if you have Selection on pressed rather than Image. I think you have Selection.