Please someone help me...
From the symptoms the possibilities of oral melanotic macules need to be ruled out. In this the lesions vary in color from tan to brown to dark brown, and they have irregular borders and skip areas. You cannot remove them at home. Cryosurgery using liquid nitrogen and laser are the main treatment modalities. Although there are many skin creams like hydroquinone and salicylic acid, but their use needs prescription .
I suggest you to consult a dermatologist and get it evaluated. I hope it helps. Take care and regards.
and also, although im sure this is completely irrelevant, if you bite your lip, say when you get nervous or your thinking deeply about something, QUIT IT! that can cause those spots as well, i used to have something that looked equivalent to what you have there in that picture and they went away after about a month of not nibblin my lip! :p Good Luck!