Welcome to the forum!
Yes.
What I mean by that the two choices in your question are not mutually exclusive. Your field could be working for you AND you could be overusing it.
If you’ve read our Official Sapienmed FAQ (Updated)*, you’ll remember that permanent structural changes to our bodies are taxing to our energy systems. (That’s one of the reasons why babies sleep so much. They’re creating all sorts of stable physical changes to their bodies.) So, that alone can account for your sleepiness.
Separately, you could also be overusing your field, which could account for your sleepiness.
Or you could be overusing your field which is working and both of those together could account for your sleepiness. In this last instance, it’s sort of a 1-2 punch.
What’s been your experience when you dial back your listenings?
*If you haven’t yet, then by all means, check it out. There’s lots of really good stuff in there for you.