First of all, you should really do some homework on pregnancy, sperm does not attach to your ovaries, first sperm meets the egg then about 6-10 days after that the fertilized egg then attaches to the wall of your uterus, which can sometimes cause implantation bleeding. Which is a little like a period, only lighter, and doesn't last that long. Second, if you only had sex 2 weeks prior it is unlikely that you are having symptoms, like cravings and back pain. If you haven't gotten your period, and you are still nervous, then I would suggest taking a home pregnancy test. Good luck to you, and hopefully the outcome is what you want it to be. :d