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The symptoms (sensitive & sore breasts, headaches, increased tiredness, bloating, abdominal pain/cramps, feeling gassy, mood changes) that you describe could suggest possibility of pregnancy. Wait and watch for your periods. Look out for development of any other new symptoms if pregnancy is suspected. If you get abnormal periods, 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. Take adequate rest. Drink plenty of water. Maintain healthy diet.
Take care.