A week before my period I am bleeding, but it's very light, like not even a period. My normal period lasts 6 to 7 days, but its only last like 3. I looked it up on Google and it sounds like implantation bleeding. It started about 12 to 14 days after I last had sex. Could it really be? I have some stomach pains, but not cramps. I have been feeling slightly sick too.