Black mole type in mouth. On my tonsil.

I am having a black spot in inside cheek in mouth.it pains sometimes while i eat but the pain is minor.the black spot looks like a mole.the spot came like last night.but the pain was there as i moved my finger inside mouth it pained it felt like a area is swollen or is bumped up a little.is that a sign of oral cancer?I recently had some white spots on tonsils but the doc cured them..when i show my mouth to my mother she say there is hole type on my tonsil..and somedays back i had acidity problem..my age is 16 please tell what it is...i hope its not any kind of cancer.first i thought it might be a ulcer but when i saw my mouth in mirror i saw that black mole type thing!! i dont smoke or use alchohol.the black spot came i think last night or 1 or 2 days ago.The area pained since 4 to 5 days ago.help and tell the medicine and if i should consult a doctor and please give a brief information about this.