Sherry,

I agree with all Strike had to say about quality and getting what you pay
for.  On the other hand, I have a different opinion about what to do about
your situation.  I suggest you go ahead and finish the course, then take
your business elsewhere.  You didn't get what you paid for, but at least you
will get the card.  The upside is, you've gone through several diving
experiences which required you to deal with things you should never have
experienced while under the care of a good instructor.  Such experiences
advance your diving, just not quite the way you had hoped.

Lee