I weigh once a week, or if I think I am plateauing, once a month. I am sorry to say you are just weird
You're meant to way more after working out not less!!!! AF will definately make you hold water. If you are weighing every day, make a note of your weight and choose the most stable weight as your "official one" or the lowest of the week, whatever suits you. i'd go the lowest personally
I don't own scales, and the guy at the gym growls at me if I weigh more than once a week!!!!!