Hi well I read what you said, I have never heard about the abdomen thing... I dont think thats very reliable... Like yu could just pull a muscle and it might hurt, yu no? Well dont be too worried, when I first had sex, I was late also... I thought I was pregnant, but if you convince yourself that you might just convince your body that you are and not get your period, if in the next month you dont get your period, test again... If that says negative too, and you still dont get your period the next month... Go to a walk in clinic and ask to be tested... Its totally confidential. And hey, im in the same situation as you right now except the guy left me just before I realized this... Well talk to u soon