Keep on effing up on GChem

Hey all,

I'm taking the Kaplan Subject GChem quizes and I can't get past 80% on those 30 questions, and sometimes I take more than 30 minutes to do them. I keep on making these small math mistakes which throw off everything and get me the wrong answer (e.g. proper conversion, mistaking + for -, etc etc).

This has happened consistently for the past 5 exams I took. I'm really shooken up by this because I have a feeling it'll be the same on the real thing. I'm freaking out because its not that I don't know how to approach the problem most of the time, its because of stupid sh&t here and there.

Does anyone have any advice, as I AM trying to be more careful but to no avail is it working. Does the real exam contain just as many "trick answers"? I going nuts staying up all night trying to get past 80%...