I suddenly noticed a lump underneath the penis shaft between the shaft and scrotum. It had appeared overnight just like that. Earlier it was reddish and puffed,soft and somewhat painful when pressed. Later it grew smaller in size and harder than it originally was. There's also a lot of itching in the groin area and all over scrotum. Do I need to visit doctor? Or it will go away just like it came? Please provide an honest advice.