Thanks for your question. This is something that you should discuss with your doctor
, as there are many things that could result in this, and some of them are serious. Depending on your age and risk factors, your doctor may be able to help reassure you greatly, and will definitely be able to help you with your problem.
Perhaps the most common cause would be oral hygiene, as gingiva and other areas around the teeth can bleed when they are inflamed and not healthy. Diet can play a part in this as well. Beyond that, there are many areas in your mouth and throat that could bleed. Some people will have problems with their tonsils, and rarely people will need to have their tonsils removed for this reason. There are other areas such as the vallecula, epiglottis, and larynx, but none of these would be prone to spontaneous bleeding
unless there was a tumor or something abnormal. It would be hard to say more without a physical exam and the ability to ask some additional questions. Speaking with an ear nose and throat surgeon
, AKA ENT AKA otolaryngology-head and neck surgeon may be a good first start. Please speak with your doctor.