If you can, keep an eye on the wound. Do you know if he had stitches or disovable stitches? (if stiches, you should of been told he'll have them out?)
If it bleeds, id be back to the vets :wave:
Biccy cleaned his wound a lot and ended up with a haematoma (blood filled pocket) in one of his scrotum sacks, but this went on its own after a couple of weeks.