I have dark purplish spots on ethe backside of my penis. I am 15 i asked my dad and he said it was nothing. I am really scared that its a form of cancer. These spots go away in bright light (when i light ir up with a white flashlight) it almost seems like there is less blood getting there cause when i slightly squeeze it they arent visible. When erect these spots strech out but are slightly lesa visible. Please help me i am really scared that this is a cancer and my dad doesnt really let me go to a dermatologist for this "cause its nothing