Preparation vs. Procrastination

Why is it no matter how much time is put into preparing for an entrance exam I always feel unprepared... Well, I haven't taken the exam yet, but I already feel unprepared. I've been taking practice tests, reviewing notes, studying from a HUGE review book, and taking online practice sets. Perhaps I will do better than I think... Last time I took it I had less knowledge (hadn't taken Physics 221/222, Organic Chem, etc. which are major sections of the exam). But still afraid it was in one ear and out the other... I'm just looking forward to improvement over the guessing method employed previously on those sections. Also now fearful of the "Quantitave Reasoning" section of the exam. It has been 12 years (yes, 12 years) since I had Algebra. I find myself begin able to work the problems, but it takes much longer when I cannot remember the formula to simplify it. Also, a calculator would be handy... but, alas, calculators are not permitted. Leaves a lot of room for my calculation errors. ARRRRGGHGHGHGH!!!

So that's my view of preparation thus far. Frustrating! Procrastination is much more fun... and then you have an excuse for lower-than-expected scores!!! :)