Hey don't get your motivation down!
CNA is a very though you are right but it is worth it.
Your talking about a job that can literally save people life - so don't give up on it.
Like other people comment here I recommend you to prepare yourself with some online resources like CNA Practice Test and after you feel enough confidence answering the questions right go to take another exam and we wish you to pass the first time.
God bless you and good luck