Should I Be Concerned About Ear Swelling After Getting Hurt With A Baseball?

My son, age 6, got hit with a baseball that deflected off of a post and hit him in the ear. His ear is swollen to about 1 & a half times the size of his other ear. We have a cold compress on it, and it didn't hit him that hard and he seems okay and says the ear stings when I touch it. I know I'm probably worried over nothing, but I've never seen an ear swell like this. It's like the top of the ear grew higher up toward the top of his head but the bottom of the ear is the same size it always is.