Vein in back of head


For the past year waking in the morning is worse, the back of my head in one particular place is throbbing with pain, most nights it wakes me up and i have to shift my head in a different position to stop the throbbing every time my heart beats, it hurts.

It goes away if i move my head into a different position then comes back if i move my head back almost as if i can trap the vein and block it and make it throb I’m really worried about this because it seems to be getting worse self clicking my neck seems to help, i think im really worried its a brain tumor

The image uploaded (red heart) is the exact position and it feels deep not on top of skin

Please can somone help