Hi Thank you for asking HCM. I have gone through your query. The bump present on your penis shaft is most likely a boil. If you send a picture of it then it will be more helpful for identifying. If there is pus accumulation draining of puss will be necessary. Applying betadine ointment will be helpful also. Wash the area with warm water or saline. If more bumps appears then it is better to consult your GP or dermatologist to rule out genital herpes. Hope this may help you. Let me know if anything not clear. Thanks.