Healing Tool Not always showing the Arrow/Circle control

Often when using healing tool, the circle/Arrow tool ( O---> ) does not show up so the sample area can be readjusted. This seems to happened when there are several being created. To compensate, I end up creating another layer, but that takes from the 16 layer limit. So far, I have not found a way to refresh to see all the instances of the control. The healing does work, there is just no control to tweak the source.