It's only impossible, until it's done.

Same feeling i got after i passed my NCLEX 2 years ago. 

If you are faced with the question of "Should i take it now?" Answer is yes.

Take the opportunity and if you fail, retake it!  Don't think that it's too late to take it or you don't have time to do it because you know you do. Make time.

What a great feeling to get this off my goals list this year. Finally a certified critical care nurse.