Account Picture Looks Squashed

Recently, I've noticed that when I log on to my computer (or awake from sleep), my account picture is suddenly rather squashed and wide. Now, given that it's a picture of me, the picture is already wide enough when displayed at normal size, so if there's any way to remedy this weird issue, that'd be great. I already went into Users & Groups and reinserted the picture, which worked for about a minute, but then reverted. So any solutions would be great. Thanks!