Is the skin over your scrotum otherwise normal ?
How much bleeding did you notice ?
This spontaneous bleeding can ocur spontaneously from a skin fold on the scrotum because of fragile scrotal skin that becomes thinner with age.
As there is no sign of infection or a skin lesion over that area, this is most likely from ruptured fragile skin.
You can apply OTC Antibiotic ointment like Neosporin over the area to prevent an infection.
Wearing padding under your inner clothes would help apply gentle pressure over the area and prevent a rebleed.
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