If you bite your tongue, you may develop a sore that can last for days and be very painful. A minor infection on the tongue is not uncommon and can cause pain and irritation. Inflamed papillae, or taste buds, are small, painful bumps that appear after an injury from a bite, or irritation from hot foods. A canker sore is another common cause of pain on the tongue. This is a small, white sore that can arise for no apparent reason. Canker sores may be caused by a virus, in that case it is called a viral ulcer. In many cases the cause of a canker sore is unknown and referred to as an aphthous ulcer. These sores usually go away without any treatment. Other, less common reasons for tongue pain include cancer, anemia, oral herpes, and irritating dentures or braces. Neuralgia can also be a source of tongue pain.