I have a small canker sore looking thing on the inside of my lower lip. not painful. it looks more like a blood blister rather then a normally white s?

7 days vs a week: There is a joke in dental school, that with medication it takes a week to heal, and without, 7 days. However, there are some things that are helpful. If you frequently get these, try the supplement lysine daily. Avoid acidic foods and crunchy items that can irritate it, like potato chips. Rinse with warm salt water as a palliative measure. And there are OTC palliative salves.

Canker sores: Canker sore are generally somewhat painful. It may not be a canker sore and you might be correctly calling it a blood blister if you accidental bit your lip. See your own dentist for a definitive diagnosis.

Is it a canker sore?: Maybe harmless mucocele (blood blister). Usually they're not a problem and will go away on their own. If concerned see your dentist for evaluation and surgical removal.