One day I found a small bump on the head of my penis. It was the same color as my penis slightly red due to the enlargement of the bump. There was no pain or any other types of symptoms. After a few days it started to go away. As it got smaller, I notice there was a tiny black dot in the center. Then finally it went away which took a week from start to finish.
A week later, another one appeared on my penis head but at a different spot. Same situation where it's going away and then the black dot appears. Can anyone advise what this might be? and if it may be an STD?