My 20 month old son feel off a jungle gym 2 weeks ago and hit his head on concrete edging. He had a large indentation on the left side of his head above his ear. Other than crying a short time, he had no other changes. I took him to ER and we decided against a head ct due to no apparent changes. The day after it happened, a hematoma developed (a little bigger than a quarter). The hematoma is now gone but he has a golf ball size area that is squishy and feels rough and bumpy around the edges. I was wondering if he could have a serious injury. Also wondering if this will ever go away or any things to watch for as far as side effects of injury.