@ This is enriching advise well beyond LSAT preparation.

Hey boss, don't worry as this is nothing too out-of-the-ordinary. After I took my diagnostic exam, it was a full month of practice or more before I even beat that original score. The reason is that I was constantly stressing during my early exams and felt an expectation to improve every week, which wasn't conducive to dispassionate and relaxed cognition. For me, I just practiced untimed to build up confidence.

Remember that bad days certainly happen, and from an outside perspective, it doesn't seem like something worth worrying about. The only harm this can cause is what you allow it to. In fact, use it as an opportunity to learn about yourself. I would venture to say you might be falling into a similar trap as myself and others with worrying excessively about the need to perform when what we often need is just to take a step back and focus on the process more than the score.