Lecture time. You REALLY should use all your points each day. Under point is BAD. If you don't eat enough, you will get the opposite result from what you want. The body doesn't think you are going to feed it properly and holds onto the calories you give it. You really should trust the WW folks who formulated the MINIMUM points for your weight range.
If you need extra points, I suggest activity points. It's not really the right way to look at it, but I've been known to work out for a doughnut!