It is possible you either switched from v2 to v3 or the other direction.
Symbols

Easiest way, not knowing which version you are on, is www.chess.com/switch
Huh, that's not it. I was always in new chess.com, it's just the symbols switched. For example, when I analyze a game, it has letters instead of arrows for the next move. Right now, the symbols at the bottom of the page are S,F, (maybe a Chinese character), trademark symbol, Y with two lines through it. Help?
My symbols for tactics and other buttons on my website just changed. I fear that I changed it on accident. Did I and is there a way to change it back? Did this happen to anyone else? Thanks.