Hello Donna,
I sent you an e-mail but of course I did not read this question on this site first, make sure you have your tensions set where they should be, top tension between 4 and 6 and make sure the presser foot is up when you thread the machine, you should be able to just pull the bottom thread through with some resistence.
Ken
drivewithken@blueyonder.co.uk, September 2008