I have a blood clot on my upper left lip by my cainine sometimes i feel it and some times i dont?

RU sure it's a clot?: Blood clots don't persist in the mouth. They usually heal quickly, but can recur if factors leading to their formation remain, e.g., a sharp tooth or repeated lip biting. A persistent blood-filled lesion would not be a blood clot, but some other vascular abnormality, such as a hemangioma or varicosity. You should arrange for a formal diagnostic visit with your dentist to determine its significance.