Almost 2 Weeks Ago I Noticed A Small Red Bump

almost 2 weeks ago i noticed a small red bump on the tip of my tongue, it eventually turned into a white/clear circle. it feels like a canker sore but ive never had one that looked like this before. now it has another red bump beside it and when i gargle with salt and water it almost looks like there is a darkened spot in the center. what is going on? may i also add, im 33/34 weeks pregnant