Not necessarily. You can be service connected for any condition that occurred during, or was aggravated beyond normal progression while entitled to active duty pay.
You may want to read the notes from the C&P evaluation. Was there a particular stressor during your active duty time that you think may be related to your current symptoms?
I am having the same issue. I went through a very stressful PCS and separation from my family. Started suffering from anxiety/depression and suicide. A year later they diagnose me with PTSD from childhood trauma and chronic adjustment disorder. My doc wrote up a P3 profile and recommended the MEB. then I find out the MEB doc kicked it back saying it is EPTS and they won't start a med board. I'm trying to find out more information. But as far as I see it, no matter the childhood history, the stressor happened while in the service and therefore is service aggravated. At the very least. Let me know what happens with your situation. best of luck.