i feel your pain! they look alot like the curtains i made for our bedroom in our new house :)
luckily for me i had 2 sets of windows to cover so when i noticed one was 4" shorter than the other i then went back and made 2 more just like them...then paired them up to match. it has taken me YEARS but i finally started (doing the math) when i sew ... well some of the time anyway ;)