Hello, could somebody help me with this expression please?

[Solecito-D]

Hello everyone, I have a question.

Frequently, I hear that people says something like : I have had a thoughtful day! what do they mean?

thanks.

[Calis]

Errm...I've never actually heard that used, but I'd say it means lots happened in the day to think about.

That meaning is just my interpretation of an otherwise meaningless sentence.
By the way, who have you heard who says that?

[Not a teacher]