Also a clean container and a hose on the bleeder can help "see" if it's air. Fill the container with brake fluid and put the hose into it, you will see air bubbles.
But I would make sure the pads are not "tight" in there mounting points. They need to slide.
I will also say, in some cases, If you have rear drums, if not adjusted correctly can also cause pedel to drop and you can pump it up.
Have you done anything to the brakes, like replace the shoes, drums, rotors, or pads? Wheel cylinders, or calipers?
Last thing, does the master have it's own bleed screw on it. I have seen lots of fords that uses this, and will also cause problems, but don't recall seeing it on a contour or mystique.