Have you noticed something odd about the message list?

I got a notification that I had 2 new messages. When I entered the message area, it did not display in the usual way. There was just a row of numbers across the top. When I selected 1, the newest message, nothing happened. When I selected 2, I got a copy of the most recent of the previous messages. When I select any other number, I get the usual message display format as before, but starting with the selected message and not including any more recent messages. What’s going on?