Had unprotected sex on 7th, 8th, 9th of August as soon as my period finished. I had flu like symptoms a few days later and felt sick.My joints were really aching aswell and having bad headaches. On the 22nd i started to bleed but its brown and experiencing stomach cramps rite now. My period started 5 days early, is this anything to worry about and do u all think i could be pregnant??