Why do I have a big Q on the upper left of my screen when i go into a text?

Just had this happen to me today. I can't even pinpoint what I was doing when it appeared. A re start of the phone cleared it. I'm super curious to know what this is!! Doesn't seem like it's happened to many...yet.

ME TOOO!! omg it's so annoying. I have only had this happen with an iphone 4, and i noticed it started happening after I did a text msg. usually it's just a big Capital " Q", in a similar position as it would be on the keyboard. but it stays on the screen. Now it also stays there even when i go to my home page or any other screen for that matter. I recently had my phone swapped out because my home button had worn out (uh oh....less than 6 mo old too!) but even on the new phone it's doing the " Q" thing too.

mine only goes away when i reboot. grrrrr. glad im not the only one tho.