11 month old got a black eye

Spare me the guilt trip, but my 11 month old was practicing his walking and pulled a TV tray onto his face and gave himself a black eye. He got hurt on Friday and the bruise didn't show up until Sunday. It's weird because he only cried for like 5 seconds until the shock passed and it still bruised.

Do any of you have a good remedy for baby black eyes?

UPDATE: Thanks everyone for your kind words. As a mom I get that it happens, but as a social worker I kinda freaked lol. It better clear up before his first birthday on the 22nd! lol