This is a bit hard to describe, but I will try-- over the last while I've been noticing something really strange happening--
every once and a while, I will be sitting up, and feel pressure start building around the back of my head and down the back of my neck. It almost feels like the area is swelling or something, and then all of a sudden it feels really heavy and swollen, and somewhat uncomfortable--
then I feel this strange sensation deep inside the vessels that feels like fluid is quickly draining from my head, down the back of my neck (but deep inside)-- it isn't really painful, and only lasts a few seconds-- sometimes I can almost hear the fluid draining. Its kind of been making me wonder what is going on because I don't remember always having this phenomenon occur. Does anyone else understand this, and possibly have experienced something similar to this? If so, do you have any idea what it is?