What are the symptoms of cancer of the mouth, i have knot in my cheek?

Non-healing ulcer: If it is visible outside your cheek in front of your ear, it may be a parotid mass (big salivary gland) - 80% are benign. If it is in your mouth then a non-healing ulcer or sore that has been there for more than 2 weeks should be checked. Cancer of the mouth in someone who has not smoked or abused alcohol is highly unusual but does happen.

Mouth cancer is rare: Any new lesions, painful or not, that arise inside the mouth should be checked out by the doctor if they're lasting more than 2 weeks (especially if you smoke or chew tobacco!). Most harmless things like canker sores go away within 2 weeks. The knot in your cheeks is most likely not cancer, but get it checked out anyway if it's not going away.

Knot=get it checked: Any lump which sticks around for more than a week deserves a medical exam and likely a biopsy. A knot in the cheek could be any number of things, most of which are benign however. Ulcerations or sores on the skin or in the mouth/throat are very concerning, especially if you have a lump or knot anywhere in the head and neck. See your local ENT asap.