MASTURBATION - SORENESS - WORRIED!!!!!!!!!!!! cancer? age 17?

Could somebody help me out here im extremely worried, i masturbate a lot, well twice a day, most days, and have done for about.. a solid 5 months now, give or take a day or two, anyway, lately, over the last few days, and maybe a week ago, i think, iv noticed that after ejaculation i get sore, around the areas that the sperm touches, and very red, this fades after a few hours, after cleaning it, but the centre of my penis has started to get sore, most of the time, sometimes from urinating, (the hole in the middle) its quite sore and uncomfortable, whats worse is my imagination, i keep picturing myself having it removed because of cancer, i constantly examine myself, down there, every millimeter, there are probably other signs of cancer too, but how likely is it, that i could get penile cancer at age 17

Also wondering what else it could be.