Huh, I guess I'm more out of loop with the science community than I thought because I was sure that scientists had settled to agree that energy restoration and regeneration were but a small part to the reason behind sleep. Leaving the major reason to be that it is when our brain "teaches" our body or even itself what it learned since its last time of sleep. Hence the whole REM cycle to prevent us from moving and how a soccer player will typically dream of a soccer ball or my own unofficial theory of how those dreams where it feels like we are moving in slow motion is more of "systems check" than a odd dream where we're trying to escape a jack-a-lope...
But to get back to the topic of the OP, reiteration of get more sleep somehow (power-naps or even 12sec-5min states of serene breathing can do well to replace any lost hours of sleep (they just require extreme mental discipline)), do something about the swelling (neck rolls/rotations work supremely, even stretching down to the fingertips helps alleviate head pressure at times), and if it persists a physicians insight is always recommended. However, if meds and paying for common sense aren't ideal, remembering that head pressures are some irritation of either swelling or fluid build up in the meninges or interstitial spaces: you might wanna consider diet and exercise modifications (more running/jogs; less salts; half an extra helping of greens; and water through out the day).