(((((((((((((Andy)))))))))))))).
I posted to you under the New Members forum, but I'm glad you posted here, too. The fatigue may be a drainage issue. Even if your pressure is "within range," you probably have some sensitivity to varying pressure, so a change in position or even a change in air pressure from weather can make the brain whine. A slight adjustment in pressure setting (if you have a programmable shunt) may make all the difference. Mention it to your nsg. You don't have to live like this.

It could also be, as you mentioned, a "getting used to" issue, which should be overcome in time, but mention it, anyway, to be sure.
I have lived with hydro all my life, so I can answer other questions for you, just holler.

(I haven't had the opposite side abdomen irritation prob, so I can't help with that. someone here or on another forum may be able to, though.)
Good luck!
LIZARD