Should I reschedule my NCLEX RN, Kaplan scores are not consistent

I graduated in Dec, and I'm scheduled to take the NCLEX next wed, and I'm really afraid that I wont pass. 50% of the time I feel i'm ready and the other 50% I'm feel that I'm not. I finished taking Kaplan class 2 weeks ago and my scores are up and down. I got:

61% on the diagnostic

60% on question trainer 1

57% on question trainer 2

47% on question trainer 3

these were taken before i took kaplan, then I got

67% on the NCLEX readiness test

63% on question trainer 4

57% on question trainer 5

61% on question trainer 6

havent taken question trainer 7 yet

and my overall qbank percentage is 59% (scoring high 50's to mid 70's) and I have about 300 questions left in the q bank.

I read the rationals on every question and I watch some of the videos and parts of the book, the the sections I score the lowest.

My questions is should I reschedule? the earliest I can reschedule now is in february, and I don't want to wait too long to take it because I'm afraid I'll forget information. What were some of the scores you were getting with Kaplan and did you pass the nclex?