You're laying there, trying to sleep, and all of a sudden life sucks. A constant, uncomfortable, sometimes painful feeling starts emanating from there and it will not go away. You try and shake it off to stall it until morning, but nope. Trying to shift to a more comfortable position, especially on your side, only makes it worse.
It only eases up when you sit up. You then notice just how thirsty you are.
It's one of two things, one of which is much more miserable than the other. Either way, it'll shortly land you in the restroom for the next hour once you've inevitably given up on sleep.
I just hate things right now...