Photoshop CS3 problems

So a few weeks ago, something happened to my Photoshop and now it's really messed up.

You see, when I would make gifs, I'd use these settings:

Gif>Perceptual>Diffusion and edit the colors and the lossy. Usually with this, I was able to make gifs with up to 22 or 23 frames maximum. They'd look fine, like this:



But now, when I use the same settings, my gifs look like their colors are just mixed together and it's really ugly, to be honest. Example:



I've tried using the other settings as well but they're all the same, only with bigger gif sizes.

If anyone knows how to fix this, I will be eternally grateful.