The Waiting is Over (or is it?)

Finally on CD 51 she appears! I spotted a little last night and then this morning I thought I was in full flow force so I called the IVF nurse. I got my schedule and should start my BC Sunday. But now I go to the bathroom to check on things and she's gone again. I was on Prometrium to make me start so I'm wondering if this was a false alarm and the real one will be here in another week. I just finished the last 2 pills last night and they said it usually won't show up until 7-10 days after the last pill. Anybody have any words of wisdom about this situation?I really don't want to leave the nurse another message and say,"Just kidding!"