I usually have heavy but irregular periods and I've been having spotting recently for the past week. My last heavy period was about 6 weeks ago. I have been having unprotected sex regularly with my fiance. I have took test but 5 have came back negative and 2 have come back faint positive. I have got the symptoms of bad back ache, needing to go to the toilet more often, migraines, weight gain, boob tenderness and loss of appetite. Could this be pregnancy?