Jumping from 2,610 to 2,810 calories and gaining 1.35 kg—am I dealing with inflammation, water retention, or did I simply push things too far?

Hello, I've been adjusting my calorie intake for several weeks to achieve the much sought-after maintenance. Every Sunday, I step on the scale, hoping to see signs of progress. Normally, I increase by 100-200 kcal, but two weeks ago, when I saw I had lost 600 grams, I decided to take a leap and go from 2,610 to 2,810 kcal. After a week with this new intake, my weight shot up by 1.35 kg all at once. The day before weighing myself, I intensified my training and added half an hour of running or jogging, which left me with sore muscles. I have read that muscle inflammation can cause weight gain, but I don't know if it is enough to explain such a sudden change. Also, the day before, I feasted on 2.785 kg of cantaloupe, so I imagine that part of that extra weight is water (I went to the bathroom several times that night; by the time I weighed myself, I had probably already eliminated quite a bit of fluid). I also take creatine regularly, about five grams, although it has never caused such a big change before. The fact is, I don't know what to attribute this sudden increase to. Should I reduce my calorie intake or maintain it and wait for my body to adapt to the new training routine? What other recommendations would you give me? I appreciate any advice. I am a 22-year-old male, 1.75 m tall, I train for an hour a day at moderate to high intensity, and, as I mentioned, I am now starting to run or jog for an extra half hour.