I thought i'd ask before visiting my unapproachable doctor...

I recently developed a small spot within the 'crease' of one of my bottock cheecks. Rather than disappearing, this spot became a couple, and they began to itch.

The spot has become a 'rash' of spots in a 'ring' almost, around my buttocks. The area inside the circle of spots has become dry, sore and raised and is now becoming very uncomfortable.

The spots are still there, but hard and bigger, they are impossible to remove. The whole area is itchy and red constantly and has been for a few days.

Any ideas before I have to 'moon' my doctor?

Thanks