Gobbling a handful of treats yesterday is not going to cause you to gain 3/4 of a lb today. It simply isn't that linear and does't work that way. For you to have gained the weight from what you ate yesterday, you would have had to consume an extra 2625 calories over what your base level of calories is, and your body would have had to process them and convert them to fat by this morning already.
Most people psych themselves out this way - weighing themselves and basing what they see on what they ate 12 hours ago.
What you weigh is affected by so many other things - what you ate last week, what you ate last night, what your hormones are doing, what the weather is like (seriously - barometric pressure affects your weight), how much salt you've had, how much water you're retaining ... etc.
Here's what I do. I weigh once a day, every morning, right after my shower. I change my ticker on Mondays if there's something to change. My ticker weight is *always* based on my most recent Monday weight - whatever that might be, up or down. That way my ticker weight doesn't get affected by daily fluctuation (and besides I just don't have time to change my ticker every time I retain water or whatever!

), but I still keep an eye on where I am daily.
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