Undo the needle clamp first of all to get the needle out, turn the balance wheel backwards there may be thread jammed, failing that take out the bobbin case and have a check, if the machine turns put a new needle back in and test sew on straight stitch, if it does not sew it will need retiming. I have timing instructions, type my email address as you say it not as you see it.
Ken
kendourof at yahoo dot com, June 2013