One thing I have learnt about sewing, is that if you're not 100% happy with something, it is better to try to fix it before you go any further.
That's why this handy little 'unpicker' is my best friend in the sewing kit. I'm making a large colourful patchwork cushion for a boy's birthday present and decided to try a pillowcase style opening in lieu of a zip or buttons, but it hasn't worked out the way I thought it would. So I guess it will be a night in front of the TV with my handy little unpicker undoing all the stitches.
Oh well, there are always moments of frustration when you sew, and redoing it is just part of the process. It is much better to do something well, then when it is finished there is a good feeling of accomplishment.