Honey, you can get pregnant anytime during your cycle, as sperm can live for days inside of your body after you have sex. Wait until you've missed your next period (I know it'll seem like it'll take forever) and get a pregnancy test from your local drug store. There is no such thing as a false positive, because your body will make the hormone needed to be detected by a pregnancy test only if you're in fact pregnant. You can try a pregnancy test sooner, but it's only the most accurate if you've given your body time to make the hormone, if it is making the hormone that is. Good luck, and remember, if you are pregnant, there's many options other than abortion if you're unable to be a parent at this time. Your local doctor or family planning agency can help you at any time.