Why would a couple of doses of tripple bufferred aspririn always cause a couple of days of bleeding with bowel movements (long history of this)?

Live and learn... Your "long history of this" repeatedly proves the point that Aspirin is a platelet inhibitor that promotes bleeding. The question is not will you bleed by taking "a couple of doses" of Aspirin but from where do you repeatedly bleed? There are many benign and malignant causes of bleeding that Aspirin can promote. Please don't delay further getting evaluated--go see your doctor this week.