2 weeks ago I had hip surgery. After it I had a burning sensation in my scrotum for a week. Then a few days ago a blackish/brownish patch of skin developed on the left side of my scrotum and it leaks a yellow pus that smells horrible and the area has a burning sensation. The patch is big and hard and can be picked off. I am also a virgin so not an STD. Can someone please tell me if I should be worried.