While my prayers and good wishes are with you and your son, it would be imprudent not to take him to the ER for a look. I am sure that by now he should be okay, but the real danger in such cases is the occurrence of what is called a "lucid" interval followed by further deterioration in the condition of the child if he has an "extra-dural hemorrhage" (i.e. bleeding outside the brain but within the skull cavity ... a situation that is as dangerous as bleeding within the brain).
Remember this in future: in any child with fall on the head, at least one visit to the ER or his doctor is an absolute must. and it must be within 2 hours of the injury