I used to have so much emotional response to seeing fluctuations on the scale. but I've learnt over the years to see it as daily lessons. rather than caring about the increase, just do some reflection on the day before and use it as a tool to learn. Consider the food you ate, your hydration intake. your salt intake, stress, hormones, even going to the gym can sometimes show an increase in weight on a scale. do some reading on the difference between weight loss and fat loss. you'll see that fluctuations are an absolutely normal and necessary part of the process because what you really want is fat loss. it'll help you to take the emotions out of it.