helloo...read thru ur query...accoeding to me bleeding can cause on the extraction site if the healing process has not yet complete or it may have infected due to some remnant tooth parts or bone pieces...so it cause cant be predicted without seeing the clinical situation..but with these symptoms u can take medicines(antibiotics amox for 3 days)as prescribed by ur dentist..and take care not to have hard food and dont bite in that area for few days..while brushing dont touch that area..also dont touch that site with tongue or finger..do salt water gargle twice daily ..and see for few days and still bleeds meet ur dentist....and be cooll...hope ur benefitted something from this reply..have a healthy day!!

Thanks for your query, I have gone through your query.
The possible cause for the bleeding from the extracted site could be infection of the gums secondary to the deposits or any chronic irritation to the gums or the other cause could be bleeding disorders like thrombocytopenic purpura.
Consult a oral physician and get your teeth cleaned once. Get your complete blood investigations done including INR, to rule out any bleeding disorders. You can use topical gum astringent like stolin gum paint over the bleeding gums, which prevents bleeding.
I hope my answer will help you, take care.