Consistently Scoring in 50%'s in Kaplan

With 2 weeks and 3 days until I take NCLEX, my anxiety level is increasing. I keep trying to tell myself to relax, but I am consistently scoring in the 50%'s on my Kaplan Qbank and NCLEX-RN review tests 1-3 (52, 53, and 54 on those). I don't know what this means. If you get in the 50's does that mean you don't have a good chance of passing? Most people seem to be in the 60's. I've only made it that high once or twice when I do 50 questions in Q-bank. Am I doing something wrong? Please help!