There's a spot on my cock!

There was a girl swimming in front of me the other day as I did my laps. Whenever I had my head under the water and she was kicking her breaststroke I could see her cunt as the water had made her bikini bottoms a little too big for her. I found it was pretty erotic just to get a glimpse. My cock started to strain in my speedos and needing some release I decided to go for a steam. I usually steam naked at the gym in any event but as it was quiet I decided to have a wank. And that's when I discovered it! A lump on my cock. Well more of a spot really. It going away now but it gave me a hell of a shock.