Last weekend 5/4/13 & 5/5/13 I busted my boyfriend whose in the military and we had sex a few times that weekend . Last night my stomach was upset and today 5/12/13 I've experienced some cramps and slight bleeding . Brownish . I missed two BC pills so I'm not sure if this is implantation bleeding or spotting ? Someone please help me ! It was unprotected sex by the way .