Hi and welcome to HCM. It might be irritation or injury
,but it should heal after 5-7 days in this case. You dont need to have STD
virus can be transmissed by hands and other ways of contact.
This isnt anything serious. YOu should continue clean it and wait for a week,if symtoms persist you should visit doctor for specific creams or lotions. If you have pain while urinating it can be caused by uroinfection. In this case you should do urine analysis and urinoculture as well.
Wish you good health.