Why is there a wheel symbol on the bottom right corner of a text message I sent?

[AC Question]

I sent a text message and didn't receive a reply, so I looked in my log to make sure that I sent it and I did but on the bottom right of the envelope there is a small wheel. What does this mean?

 

[srkmagnus]

Could you post a screen shot? I'd there's any sensitive information (ie the text) then please blur that information out of the screen shot.