Sometimes you just have to get up and move away from your sewing machine. When I find something like that happening again and again....it's my clue to get up an do something else for awhile. If you got 2/3 of the way through, you must have been cranking....give yourself an hour....go back, change the needle, rethread the machine and take the bobbin out and put it back in...and then start again. I find that sometimes the machine and I just need a break!!