What to do?

My LB (16mnth) has fallen this evening, he fell hard, he was running and tripped over toy and landed funny on his arm. Initially he would not move it or use it. He cried for about 10mins 😭 and then cuddled into me for another 15mins still reluctant to move it. He then seemed fine, he was moving the arm, using the hand and did not appear to be in any pain when I felt to see if anywhere was painful. He has since fallen asleep so I put him to bed. I suppose my question is; do I still get him checked out, or do you think he is okay? Could he have really hurt himself and just be carrying on?