did you 'quilt as you go'? and maybe sew thru all the layers at once? maybe you weren't real careful with your seam allowance? this would do it. you can fix it. slip stitch it by hand, and then add some more quilting in the middle of the blocks. i read somewhere that quilting should not be any further apart than 4" and that's what i try to remember. beautiful quilt. nice colors. we learn from our mistakes.