I dropped my pill and can't find it...what should I do?

I am on my 3'rd week, dark blue pills. I dropped one in the couch and absolutely CANNOT find it. The pamphlets all say to take two when you skip one, but I can't take two cause one is missing. Do i just take tomorrow's pill? Will I still start my period this month when I get to the "blank" ones? PLease help.