This seems to be a bug in 4.0.13. From the forum:
In SQL Developer Version 4.0.0.13 , the Timestamp is showing incorrectly in the SQL History window
SQL for today - 03-JAN-14 is showing with a timestamp of 01-MAR-14
Looks like the day and month have been reversed when formatting.
... with response form Jeff Smith:
All kinds of fun bugs there - they've been addressed for our next patch/release and the developer also tells me, if anything, the product should be faster and more responsive in that area.
It works as expected in 4.0.1.14, so I can only suggest you upgrade to the current version. There are probably a lot of other bugs squashed now too; it might even crash less often...