White spot behind tooth not on tooth! hurts! what could it be?

Ulceration: If it is an ulcer it should be gone in two weeks. If still present and hurting see a dentist. If you want immediate relief see your dentist now. Laser treatment on ulcers works well.

See oral surgeon: Any white lesion/spot should be assessed. See oral surgeon.

Canker sores: are the most common oral lesions. Individual ulcers typically last 1-2 weeks. The condition is idiopathic (cause is not known) recurrent aphthous ulcers is usually self-limiting. Try to keep adequate oral hygiene as possible. If concerned see your dentist after 10 days or visit today for laser immediate amelioration.