Tongue is white sore swollen and has teeth marks?

You bit your tongue: It is common to bite your tongue and this can be painful. But the tongue is a marvelous thing because it will heal very quickly. Don't worry about this injury, it will heal in a day or two. Meanwhile avoid spicy and acidic foods. Be a little more careful when eating.

Clenching: When you clench your teeth together your tongue pushes out against them from the inside and leaves indents and sometimes a ridge along both sides of the tongue. Focus on your teeth during the day. They should only touch when you're eating. If your teeth are touching and you're not eating: that's clenching. Try to get used to keeping your teeth parted when your mouth is closed. Takes ~3wks.