I have noticed some marks on the underside of my penis just below the head. They are shaped like parallel 'lines' (4 or 5 of them) across the underside of the shaft...sort of like stretch marks...mostly in the soft skin below the head. They don't hurt, but they have not always been there. I also have a fugus in my groin area being treated with Nystatin/Triamcinolone cream. The nurse wants me to use the same cream on these marks and to abstain from sex until they are better. She doesn't think they are warts. Maybe yeast infection, but she's not sure. What do you think these are?