Weighing yourself will give you an objective weight at a point in time. Unfortunately the amount of water in the body is very variable and water is heavy. So at each weigh in your nominal weight may be up to 3 pounds above or below your long term average weight purely due to water balance. This is not an excuse to go into denial and claim you are retaining water.
I find it fascinating to see how the body varies in weight over time, so at the moment I'm weghing quite frequently, but I don't obsess about a single measure. Maybe when I get nearer the goal I might worry a bit more.
save the planet - it's the only one with chocolate