You can have several pounds of water fluctuations in any given day.
The scale is not a good tool for every day; it is a trend tool over time. The more you weigh and the taller you are the greater the fluctuations.
Water fluctuations are caused by increased water intake, lack of water intake, hormones, muscle soreness, food reactions, food digestion, food allergies, any allergies, sodium, stress, and the list goes on and on and on.
The scale is only good for a TREND. For some of us that trend happens in SEVERAL WEEKS and MONTHS, not days. The body randomly has whooshes and gains; we have not much control over this. The body does not lose fat in a linear fashion. Rather, it falls of in "chunks", quite randomly, when and where it chooses to shed it.
Everyone loses mass at a different rate. Just as it took several months or years to gain an unacceptable amount of weight, it can take two or more years to lose 50-100 pounds. That is a lot of seeming like nothing is happening for long periods of time. If nothing seems to be happening for 2-3 weeks at a time sometimes all you can do is be patient and keep doing the process.
If you had been stepping on the scale regularly during periods of overfeeding, you would have seen many days where you did not gain weight (or maybe even lost weight!) even though you had overeaten during the days just before. LOSING weight follows the same non-linear course. Sometimes you will see no losses or even slight gains despite all your hard work. This happens for many reasons that have nothing to do with FAT loss. This DOESN'T mean you haven't made any progress. Always remember that EVENTUALLY, correct behavior will ALWAYS result in correct results!
We have no control other than to do the process day in and day out WITH MUCH PATIENCE. There is no instant gratification in this game, or even daily or weekly gratification, but rejoicing in any positive results you find in the process such as how you feel, how clothes fit, progress pictures that show what the scale or measuring tape don't show, or ANY progress you've made thus far - both physical AND mental!
We are all different and have our WHOOSHES randomly at different times. We are all in different phases of the process. Remember that it can be RANDOM. So do not look at what is happening for others or compare your progress to theirs. Your day will come as well if you don't give up and if you stick with the not-so-glamorous day to day grind. There is absolutely nothing sexy about the process. It's like going to college for years and diligently doing your work day after day until graduation day comes.
So take ALL your victories as they come, or NSV's (Non Scale Victories), and ride them until the next one.
Everything positive feeds on itself and everything negative feeds on itself. You decide what to focus on.
Positive things to focus on: You feel better, you know you are doing the right thing and it felt good, you ate healthy and it felt good, you mostly kept in calorie budget for the WEEK (not daily as we are all merely human), your front/side/back private progress pictures showed something the scale and tape measure didn't show, you drank lots of water and it felt good, you went to the gym and it felt good, you can feel that your clothes fit different and it felt good, you got a compliment and it felt good.
Listen to the podcasts and learn because motivation makes you feel great too! :)