Could be the huge amounts of carbs + salt you just ate.
I am looking at your diet on the 14th.
Judging form myself, dropping ~200 g of carbs 2 days in a row, and my weight dropped 1 kg.
Bloating is a real thing.
You should really start being consistent in documenting EVERYTHING you eat.
You are btw over evaluating your calorie expenditure.
1 hour of weight training will most likely not burn 700 kcal. Maybe if it was 100%.
But lets be serious, people usually take rests between sets.
If you train to burn calories, you should just do cardio.
It would be best to weight yourself every 1-3 days, to get a clearer picture of your real weight change.