You need to find out where you went wrong first. Seam accuracy and pressing are two demons that can wonk your blocks. Look at the back and measure your seams to see if you need to improve on your seam accuracy. I use blue painter's tape putting about five layers stacked.
When you make different blocks to be put together into making a larger block, it is important to measure each of them and make any correction before you sew them into the larger block. If you snowballed the "X" block, maybe try drawing a line. You really need to be absolutely accurate with drawing and sewing the line. I use this product from Omnigrid to mark the lines on any acrylic square to check myself for accuracy:
http://www.joann.com/omnigrid-glow-l...+Select+Stores
With busy prints that you have selected, no one will notice that any points are missing.