Hi.. Can understand your concern.. As per your complain due to trauma and injury caused to your son due to falling has caused trauma to the soft tissues leading to inflammation and formation of inflammatory exudate as well as trauma can lead to rupture of blood vessels leading to spillage of blood into the surrounding soft tissues leading to HEMATOMA formation and bruising.. The soft tissues also shown signs of inflammation and there can be proliferation of fibrous tissues as well as accumulation of inflammatory cells in that area which can encapsulate the hematoma and there appears to be a hard lump.. The black eye is also due to blood accumulation due to rupture of blood vessels.. As the blood accumulated gets disintegrated the bruising gets subsided.. But the lump formed due to inflammation and hematoma formation takes a longer time to subside and you need not to worry about it as it will gradually subside.. I would suggest you to consult a physician and get evaluated for any underlying bony fractures and if it is present reduction of the fracture segments and fixation is required.. In case if there is only soft tissue injury you can do alternate warm (not hot) and cold packs over the swelling.. Application of thrombophob gel contain heparin sodium will help in faster dissolution of hematoma.. In case of pain tylenol or ibugesic kid can be given.. Hope your query is solved.. If you find the answer helpful please write a positive review and click on find this answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..