pressure on skull?

whenever i stand up or if i’m bending down for a while and when i stand back up it feel like pressure is squeezing my skull. horrible explanation lmao but idk what is causing it. it lasts literally like 3 seconds but happens constantly. it doesn’t really bother me enough to freak out but i’m just curious. why would this happen? it’s been happening for like a year.

i also get extremely dizzy when i stand up