Character moves when I'm not touching the keyboard

This has been happening for over a week. I thought it would go away on its own, but it has not. When I'm walking around in the game, and stop using the keyboard, my character keeps moving. I have used different keyboards to see if that was an issue, but its not. It is not my internet either, considering this occurred even after I turned off my Wifi connection.

There is someone I know who also plays minecraft and uses the same internet that I do, but they have not experienced this at all.