When I first started on a medication I thought I could sew. I did. Only I never put much energy into threading the top of the machine. No one could understand why my tension was always off. That is til a classmate visited and I saw her put the thread in the tension discs. I had just been laying the thread there, thus it was never between the tension discs.
Too funny. that is it is funny now. I found I had to completely redo all the seams of the top I had tried to sew. together.