I took my pants off, as my foreskin was under some pain, and I noticed it looked like it was covered in a thin layer of white powder (which washed off easily). I then noticed what appear to be small cuts (presumably the source of the pain), all on my foreskin. It also seems relatively tight. I have been tested free of STDs, and I hadn't engaged in any sexual activity the whole day. What could this be? (Hurts.)