Hookah?

So my husband got a hookah about 3 weeks ago. He used to have one and he thought it would be fun to try it again. I have never smoked anything in my life. But I really like it. He got rose tobacco. Well about  5 days later I started to notice that my teeth around the gums have this yelling orange stuff around it. I do brush my teeth 1s a day but I don't floss. Could this be from that? It comes off when I brush but it comes back 
And yes I do know that smoking is bad and I don't do it vary much