I’ve got another possibility fot the 65%. You took 3 exams in a weekend and you are cocerned about your score on the last one? Maybe your brain recuperates better than mine, but I would have gotten a 26% on my third. Your 83% gives you almost a 100% chance of passing the actual exam. I think bad plan taking three mock exams in a weekend but otherwise your studying has gone great.
Just did the third Sample and another 66%! This is becoming frustrating! On the flip side, my feeling is that Sample 3 is way harder than the first two exams. Back to books i guess, and will take the first Mock in mid May.