Sweater Disaster

 
I just don’t get it.  I took the old sweater piece completely off the needles yesterday and measured the gauge and got 5.25 stitches to the inch.  So I rewrote the pattern and cast on for the new gauge.  I’ve got about an inch of the hem done, and it is just barely bigger than my 40" circular.  Not anywhere near the 54" circumference I was aiming for.
 
I’m completely baffled on this, so today I’m going to pick up a 4.25mm Clover circular at the LYS and do a rainbow-striped scarf (knit like a tube).  Once that comes off the needles, I’ll measure it and use my gauge to go from there.  I can’t remeasure the thing I took off yesterday, because Alex has been using it as a lasso and it’s all stretched out!