I just pulled a long maybe 12 inch long yellow thing out of my dogs butt SHe has worms Is it something to do with that?

It sounds like a small tapeworm since they can become very long. I hope you were wearing rubber gloves.

Although it is very rare to get dog worms in humans, you should keep your dog away from children since the dog tapeworm eggs are transferrable by fecal or oral contact or a combination of both.