Okay heres how it all started, around last week, I scratched the side of my penis with my fingernail. At first I thought it bled, but it didnt. Fast forward a few days later, I noticed that my upper left quarter of the shaft, near the head, has gotten quite raw and reddened and it seems to be affecting a larger area than the area I scratched on accident...I'm really concerned it could be something serious, like an STD, or penis cancer. The thing that is concerning me is how non specific my symptoms are, they can be literally anything.