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can affect absorption of drug. Before diarrhea your pill got 2-3 hours time to get absorbed, thus it can't be treated as missed dose. But it can definitely increase chances of contraceptive
failure. In a regular cycle of 28 days, ovulation generally occurs on 14th day, thus 8th day of cycle is comparatively safe. In my opinion you should be safe. If your period doesn't start within a week of due date, do pregnancy
test and consult a Gynecologist.
Hope you found my response to your query informative and helpful.
With good wishes,
Dr.Chandra Shekhar Sharma