BFP 3 days before expected AF....help...?

Ok... I'm very scared (it's hard for me to even admit that!) but I found out I was pregnant yesterday which I am very happy about. I tested positive 3 days before my expected period (which would of been due this saturday). Last time I was pregnant, (june 09), I was spotting on my period date.I didn't worry cause I heard it was normal for some women. But the spotting didn't go away for a few weeks, then I had a miscarriage. I am afraid if I see the same thing on Saturday I will go ballistic! I have been taking my vitamins and being healthy and taking care of myself. I just want to know on Saturday, is it normal to expect spotting, or nothing at all? I just don't want to go through another miscarriage! Thanks.