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Shorter and lighter periods, spotting could be few of early symptoms suggestive of pregnancy if you had been sexually active without protection during fertile days. Look out for development of any other new symptoms if pregnancy is suspected. If your symptoms have been persistent, or if you suspect chances of pregnancy, consider visiting your doctor/gynecologist at the earliest 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.