I've had 3 cold sores in the past month. i usually get one a year, but i have read that cold sores could indicate oral cancer. should i get checked?

Cold Sores: Ulcers can indicate oral cancer but cold sores are caused by a herpes virus. The difference is ulcers don't go away and cold sores resolve.

Only if persist: Only if they persist. See oral surgeon or ENT doc if you have any of these symptoms: Persistent mouth sore, persistent mouth pain, a lump or thickening in the cheek, a white/red patch on the gums, tongue, tonsil, or lining of the mouth, a sore throat, hoarseness or feeling that something is caught in the throat that does not go away, difficulty swallowing/chewing.