What Causes Itching On Perineum Area?

Hello doctor, I noticed about 5 days ago that it was itchy on my perineum area. I thought it would go away, but it did not. Today I looked with a small mirror and noticed it was red and continues to itch. There are no bumps. It seemed to happen after I was using the toilet paper at school when I used the restroom, which the toilet paper is thin and cheap but it could be coincidence..Please help.