hello, i have had this small red spot on the underside of my penis head for at least over a year now, the last time I had sexual contact was over a year ago but I'm 90% sure I had the spot before any sexual contact at all. It is not raised at all, just a small patch of skin that is a darker red than the rest of my penis. It does not hurt/itch at all and i cannot feel it, it's only visible. Can anyone help me? I've been very stressed over this recently so thank you for any help