Im sure it probally is nerves, it would be too early for anything else. I know you are nervous, you have just got to try to relax and calm down about this until you can find out for sure. Worrying isnt gonna get you any results any faster, know what I mean? Call PP back and ask them if they do an HCG blood serum pregnancy test. I know you are scared, I have been in your shoes, and I know it is not fun playing the waiting game.