How long before you stop getting your period, if pregnant?

sorry, guys, but there's really nowhere else i can ask this question, and i've never been so glad that the internet is anonymous (pretty much).
i last had sex last saturday; it was done one time without a condom (i ran out of birth control pills last month and haven't had a chance to go back to the doctor, so i don't need a lecture on this), and i was a little worried but then i got my period yesterday. is this a sure indication that i'm not pregnant or does it take longer for pregnancy symptoms to show and should i wait and see what happens next month?

I dont think you are pregnant,,,,,you werent ovulating when having sex were you?

If your period came, its most unlikely, although Ive known women who have had theirs and been pregnant..

Do a home test just to put your mind at rest.....will probably show negative though?

<---open--your--mind--->

Um, no, you can go to a site that has people trained to answer your question. We are not doctors here. Certainly in a matter as important as this you would want to consult professionals, no?

i was too lazy to do a google and sift through results but it looks like i'll have to...