Hi,
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The pullout/withdrawal method of contraception is associated with highest failure rates. The chances of pregnancy cannot be ruled out if the unprotected intercourse was during your fertile days. Your symptoms (changed appetite, bloating, abdominal cramps, low back and hip pain) could be suggestive of possibility of pregnancy. If periods do not start within 10 days of expected period dates and you continue to have (or develop new) symptoms suggestive of pregnancy, you should consider visiting your doctor/gynecologist at the earliest for further examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Take adequate rest. Drink plenty of water. Maintain healthy diet.
Take care.