How did a black blood bubble grow inside oral cavity to return a responsibility

A black blood bubble grows in the mouth, usually due to eating too fast, or eating dry food caused by trauma, resulting in the rupture of mucosal capillaries, resulting in blood bubbles. If the blood bubble is very small, do not worry too much, let the blood bubble absorb itself; if the blood bubble is very large, you need to go to the hospital, by the doctor with a sterile needle to puncture the blood bubble, the blood stasis inside is discharged, and then you can rinse with gargle. The above health science knowledge is for reference only. The specific situation needs to be checked in a regular hospital and judged by a professional doctor. Do not diagnose or treat yourself.