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Chances of pregnancy cannot be ruled out completely due to possibilities of contraceptive failure. The delayed periods and spotting could suggest possibility of pregnancy. Wait and watch for your periods and look out for development of any new symptoms suggestive of pregnancy. If you get abnormal periods, or if you develop any new symptoms, or if you suspect chances of pregnancy, you should consider visiting your doctor/gynecologist for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet.
Take care.