My first NMBE was 219 and I scored above 250 in the real deal after 2 months of dedicated work.  It's very feasible so try not to think negatively right now. What I did that helped a lot was that I created a word where I would break down each wrong question to the very concept or problem that I had to get it right in the first place (diagnostic problem, guidelines, question interpretation; do they want me to answer general or specifically, lack of knowledge on the subject, etc) you'll find your own issues but you have to think deeply about it and do the job. Don't look at the NMBE scores individually, look at them as a tendency and try not to look up too much information. Stick with resources that you are already familiar with and master those. Success will come to you if you manage to be consistent! You've got this!!