my stomach looks big and feels different?

Hi,
Welcome to ehealthforum,
If you were sexually active without protection during fertile days, or close to ovulation time, chances of pregnancy are possible and the symptoms of spotting, altered bleeding, back pain, abdominal pain/cramps, abdominal distention, bloating, sensitive breasts, that you describe could suggest pregnancy possibility. Look out for development of any other new symptoms if pregnancy is suspected. If pregnancy is suspected, or if you have abnormal periods, or if you do not get your periods within 10 days of expected period dates, 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 and lifestyle.
Take care.