Actually it had just been oiled not very long ago. I think it's "fixed" now though - dh pulled out a large wad of thread - and it still didn't work, I tried again, pulled out one more thread and now it seems to work. At least it stitched. And no clunking. I think the little wire thing on the tension is bent - the end of the wire was rubbing on the dial. I'm sure that didn't help. I did push it back some. Not sure how that happened, but I do have a 5yo. Although he really is good about not touching things...
I do have a friend that does sewing machine repair, but we have a huge snowstorm coming tomorrow - I was all excited about being shut in and having guilt-free sewing time! It better stay working now!