Hello Good Day Dear I would like to answer your question in detail and want your satisfaction . In the first 24 hours after a blunt eye injury, blood may leak into the skin of the eyelid and surrounding areas, causing swelling and a bruise , commonly called a black eye . The blood usually drains toward the bottom of the eye after a day or two, resulting in swelling and discoloration of the eye lid .The condition of your son as you have told seems normal and yeah its normal after surgery . This would resolve without treatment after a few days or weeks. During the first 24 to 48 hours, ice packs may help reduce swelling and ease the pain of your son. After the first 24 to 48 hours, warm compresses may be applied to aid absorption of the blood. Nonsteroidal anti-inflammatory drugs (NSAIDs, such as aspirin or ibuprofen) or acetaminophen can be given if the pain is significant. If you have any other questions , I am here to answer you . Best regards .