I have one tiny whitish sore on the inside of my lip. It's pretty small with a some redness around it. It's sort of painful. Canker sore or herpes?

Canker sore. A canker sore is a painful, open sore in the mouth. Canker sores are white or yellow and surrounded by a bright red area. They are not cancerous. A canker sore is not the same as a fever blister (cold sore).
Canker sore. Most likely it is a canker sore. Herpes are little vesicles and are very painful. See your doctor for an evaluation.