Is it a little bumpy or flat on the skin?
Wally sometimes get bruises on his nekked bits (his stomach and part of his chest has no fur). I worried because he had one that I thought was ringworm, but it was just a bruise according to the vets.
"All changes, even the most longed for, have their melancholy; for what we leave behind us is a part of ourselves; we must die to one life before we can enter another." -Anatole France