I was in a waterpark and when I went to the toilet, I noticed a lump on the back of my penis shaft. It doesn't hurt, only a little if I touch it, it doesn't itch. I'm wondering what caused this and how can I fix it? I don't want it to ruin my sex life. All help and comments are appreaciated. Thank you
P.S. if anyone is wondering I always use protection and clean my penis thoroughly.