I fell off a small wall and hit the back of my head. Went to the hospital and had a CT. They said negative. My arms went numb for a few seconds after it happened. Other than feeling a bit sleep and groggy. I am not in any real pain mostly. I have taken no medication or pain relievers. Funny thing is the one pain I do feel is a really stiff jaw. It actually felt out of place right after I landed but not now. Any advice or concerns. I was released and told to be watched every two hours and they said I could use Ibuprofen , but I am cautious.