Did you sew the strips end to end or long side to long side? If you sewed them long side to long side and sewed them all starting on the left side, then it is going to swing to the right. When I have to sew multiple strips together along the longer sides, I always sew one seam from left to right, then the next right to left, continuing to alternate. Sometimes you will still get some movement, but it is much more controllable.
This is a good pattern for the jelly roll race quilt.
https://weefolkart.com/jelly-roll-ra...ections-notes/
If you have sewed them all down the long side, you would have to undo some seams, but you could make this quilt using a half square triangle setting.
http://cluckclucksew.com/2016/10/dia...-tutorial.html