It's a bit hard so say without the broader context. The intonation does not strike me as a question, if that's what you mean. However it does suggest that he seems to think there is
more to be said about the fact that he hasn't had a clear thought since yesterday. Perhaps he's trying to think what might have caused the problem and/or what he should do about it. Perhaps you might also say that the intonation he uses in that sentence is a bit suggestive of a mix of "worry and wonder" about the uncomfortable and unfamiliar state he now finds himself in.
That's my two cents.
