In the first picture of the block it looks like a generous 1/4 inch seam. Measure the back side to make sure there is only 1/4 inch of fabric.
Check the ruler you are using for cutting that it is accurate. I had to adjust my cutting methods as the pieces were shy of the true measurement. Funny how those little bitty lines add up.
Did the needle on your machine get accidentally moved off the center needle position?
Yes, to use a g*lue s*tick to match those pesky seam lines.
ETA: There was a link on the last line so I added the two **.