My Son Plays Football He Was Making A Tackle And

My son plays football he was making a tackle and took a hit to his right leg from another player. His leg has been swelling up since then. I took him to the emergency room and they said he had a ankle sprain and ankle contusion but his leg is this still swollen could something be wrong or is there anything I can do to reduce the swelling I have tried ice packs and he take ice bath at football practice but nothing seems to work he said it stills hurt when he walks on it.