9 days after sex there are no symptoms to feel. In a lot of cases, the embryo (if one was formed) is still just floating around, not yet attached.
We have a major artery I our abdomen too that pulses. Everyone has it. And women often think they are seeing their baby's heart beat when they've had that pulse all along there. :>) And anniebrooke is telling you that symptoms are unlikely at this early time if you 'were' pregnant. You can test if you miss our period or 2.5 weeks after the event.