Do you know why the top of my mouth is yellow? and i'm scared about going to the dentist in case i have something like gum disease.. , i'm 18 and my teeth are also yellowish and the back of my bottom teeth are yellow with black bits but only visible whe

Dentists not all bad: You can't go through life avoiding dentists. Gingivitis can even hurt your heart, so buck up and get checked out. I don't have a good clue about a yellow mouth in the absence of other yellowed areas like eyeballs, so see a dental professional. Black bits on your teeth are not cool. Are you gonna wait until they fall out?

Don't be scared: You probably do have both tooth and gum infections. Your Dentist wants to help you, not judge you. You can't do this yourself. You need immediate professional help. The longer you delay, the more extensive and expensive treatment becomes. Please call Dentist now.

Multiple Issues: So hard diagnose these things over the internet, especially without being able to examine you. But a local dentist can. You're an adult now, no need to be scared. If you have a problem, it will only get worse without treatment. Seek the help of a local dentist.