What does a diagnostic score mean?

Did you just take a random PT without knowing anything about what the LSAT even is, and is that considered your diagnostic score?

I actually started the LSAT journey in March 2021. I didn’t have a curriculum, I was just taking random PTs here and there, check answers, and study off of the answer explanations. I to this day never took a timed test, and all my untimed tests were always in the 160s. Then I took a half year long break. If I take a timed test now, would that be my diagnostic?