Theres A Black Dot In My Mouth Behind My Last

Theres a black dot in my mouth behind my last moler. Theres also one on the opposite side of my cheeck. And theres a patch of them (very tiny) on my cheeck. What is this ? It doesnt hurt, i didnt even know it was there until i looked because i have a very sore throat and my ears itch. So i was looking st my throat.