It seems you might have an issue such as balanitis, a common and naturally occurring thing among men. It can be seen in a small mole-like structure on the tip of the penis that is occasionally pus-filled, and it could get inflamed and red. It could also be connected with the frequency of penis washing, or it could even be traced back to some personal hygiene habits or yet another significant thing like any irritability that might be caused by soap or disinfectant. Frequent washing and drying of the area are key to a better outcome. The application of mild soaps and the avoidance of harsh chemicals are also helpful strategies. Wearing comfortable, breathable clothes and underwear made of cotton is also good. Wear only loose-fitting clothing and wear underwear made of soft, comfy cotton. When all else fails after a week or two and the results don't get better, it is a good time to see a dermatologist, possibly for further evaluation or to control the underlying issue.