I can't tell you if that's normal...but I can tell you I experience the same thing. I don't know exactly what causes it. However, I noticed it happens when I feel that I've had enough and need to rest. When I close my eyes, they do exactly like you described...bounce around.

I think Mark said once that usually means you've gone beyond your threshold and should try to stop whatever your doing sooner.

I try to think about how my body reacts to being terribly ill...like a bad upper resp. infection or stomach flu...basically, whenever you are trying to heal, and you do stuff that your body would rather you didn't because it is busy trying to heal, it gives you signals. For me, it tends to be chills/cold sweats, headaches or just random pains in my forehead and temples, and weakness/exhaustion. When I go too far and I get a bad headache, it feels like a wound opening up in my brain...sounds dramatic, but I think that's basically accurate; I'm essentially re injuring myself.

Well i can definitely tell when i've gone past my limit, normally it feels like theres pressure on my head especially on my sinuses. Yesterday i pushed myself a bit to hard and when i tried to go sleep last night it was awful. My eyes kept bouncing around and it was REALLY irritating. Finally after a couple hours they stopped and it felt like it was kind of hard to open them

I do however, always wake up feeling better than the day before. And if im on the computer frequently things seem to worsen up so im definitely going to be taking quite a few breaks throughout the day from now on. Last night kinda sucked.