Biting my tongue?

More info needed: How long have you been biting your tongue? Are you missing teeth? Do you have false teeth? Do you have sharp or malpositioned teeth? When does it happen? Please see a dentist for an evaluation.

Depends on reason: One's primary care doctor can evaluate to find out why a patient is worried about having bit his tongue. Everybody bites his tongue on rare occasions. If the problem is recurring, his doctor will want to find out if there is a problem with the tongue size, such as it is growing bigger, or with the nerves or muscles that control tongue and chewing movements, etc...