Well a few weeks ago I ask this same question but because of a few things it was everything okay!. But because of taking the plan B my period when crazy till last moth... may 4 and 8 i had sex but with protection and we booth check the condom and everything was okay. I supossed to have my perio this 20 that right now im 3 days late... i feel some weird thing in my stomach and a little nauseous but is really rare. The 21 I did a text and it was negative... so what do you think? Please help me!!!