suspected pots but been experiencing some sort of orthostatic intolerance episodes, that sounds familiar but i can't say i know if it's always the same spot or anything. i'll try paying closer attention to it next time and see what i think

Yep, I can feel it. "Normally" (heh, screw normal), they are felt in chest, but are also commonly felt in other surface veins. The veins behind your ear are close to the trigeminal nerves and ear canal- hence your noticing of it in your head. You also have cerebral fluid which has a pressure. I get mine about 1.5 inches back and up from my ears when it's the intra-head pulsation. I also commonly get mine in my feet, wrists, behind my ears, in my neck, in my underarms near my lymph nodes, and under my knees.

I have something similar! I get this weird headache when I stand in the very specific spot (back left side of my head) and it pulses with my heartbeat. I’m seeing a neurologist for them right now.