Lost the picture of myself next to text messages

I noticed the other day in the quick settings (is that what it's called) on the swipe down menu I didn't have a picture of me and I was sure I had that on there before. I went to 'People' and set up the 'Me' contact and put my name in then suddenly my picture was back in the top left corner. But now in my text messages, the messages I have sent don't show the picture of me they used to.

Does anyone know what has happened and how to get it back?
Thanks