A central apnea is flagged whenever you pause for 10 seconds or more between breaths. Pauses are pretty natural after you've had a flurry of heavier breathing, which often occurs when you experience an arousal. The arousal breathing cleared out some CO2, which reduced your "breathe now" impulse. The real problem is the arousal, not the CA.
In any case, the number of CAs you are having is a cause for zero concern.
I'm glad you'll be having another sleep study. I also hope you're getting a medical work-up to explore other reasons for your continuing tiredness. You may need to press your primary care physician for help on that score.