ARGH (The frustration is palpable)

I scored 6/17 on mixed subject practice MBE questions today. Were the questions exceptionally hard, or am I exceptionally stupid, or have I forgotten whatever I managed to learn over the past 5 weeks? I am unbelievably frustrated and disheartened, and it's getting harder every day to force myself to sit down, focus, and study. It seems odd that it's harder as I get closer to the exam and more worried about it...but this kind of intensive study is extremely unnatural to me and I'm losing my grip.

I've also had "Hips Don't Lie" stuck in my head for approximately 17 million consecutive hours, which really is not helping in the slightest.