What should I expect if I miss my period?

I was due for my period yesterday. I have a strong feeling that I may be pregnant. I have a lot of the symptoms, no positive pregnancy test yet though. If I am pregnant, is there a chance I can still get a light period? Spotting? A little bit ago I had very light spotting, not heavy like it typically starts off as. And definitely had no signs of getting it; just wiped and it was there. Could there still be a chance? Is that normal?