Seam allowance is extremely important for your quilt to be
completed accurately. Make another block.
Less headaches further into the quilt you go.
Making another block is better than redoing it. Taking a block apart stretches out the fabric and the block will never be right because of the distortion from ripping out the seams.
It will probably take less time to make a new block than it would take to rip all the seams out.
Make sure you cut the pieces correctly, many times a block is not the correct size because the pieces weren't cut correctly to begin with.