sharp pain in the back, right side of head

[rdm9]

Pain in the back right side of my head.Feels like a nerve stinger. For the most part it is fine in the day while I'm standing up straight, but when I lay down it triggers the pain. Also have noticed that when I yawn it will trigger the pain (at any point of the day). Not when I open my mouth big though....only when I actually yawn.But sleeping or laying my head down is what really causes these pains, when I have been lying my head and neck down in the same position for periods of time. But after I wake up and walk around it usually goes away after an hour or so. This is going on the 23rd straight day of this. At first I just figured I had a pinched or compressed nerve in my upper nack and skull base....but now that I'm in my 3rd week and there are no signs of the pain diminishing I am getting a little worried. It still feels the same as it did the first day I got it.