The idea is that when you (as a developer) run into a software bug you can't fix, you try to describe it out loud to a rubber duck. It turns out that the act of formulating these thoughts into speech is massively effective as a debugging method.
So my challenge to you is to revisit this statement:
>If they asked me what is wrong, I genuinely don't know.
Instead of shutting down because you don't know, just start speaking. Keep speaking. Deliberately turn off your filter. If that's hard, narrow the question. Instead answering "what's wrong?" answer "what's wrong today?" or "what's the strongest emotion you felt last week" or etc. And then expand around it. Describe the experience. Etc.