I do see some pattern though. I am often have a "bad" set of questions. Typically, it's within 10 questions. I can score it as bad 30% correct. However, for the rest of 30 questions I can make barely two or three mistakes only. Do you think this is my bad on paying attention or something else?
On the other note, how do you prefer to study? I found myself not so happy on studying seated near the table, or on the sofa. But I like to lay on the bed with all stuff, I feel less pressure. However, I'm fine to spend a lot of time seated with laptop and it doesn't bother me that much at all.
Of course I'm missing so much the Herman Miller' Aeron chair. I wanted it and once was almost there to buy it, but something scared me off (or I just spent money on something else). Now I'm just thinking about it, but don't come closer. But I'm planning to get that one for my home office, sooner or later. It's not that expensive in the end.