Make this make sense

Ok so before I start, I understand weight loss is not linear, bodies are weird, water weight is a thing, etc. Also have done this before - losing 19kg/40 pounds in 2019 then slowly gaining it all back during the pandemic lockdowns. So, here I am in 2024. Started properly CICO and running 3-4 times a week in January. Have been slowly but steadily losing, from 85kg to 76kg so far, so 20 pounds down. Yay! But yesterday: I ran 8km/5 miles (fasted). I ate 2 poached eggs on an English muffin after my run (around 1pm). Then for dinner had a bowl of home made pumpkin and lentil soup with a slice of sourdough. Yes it was buttered but a scrape not a slab. Soup made with 2TB oil in entire thing of which I ate 1/6th - the other ingredients were leek, garlic, tin of tomatoes, celery and one potato. THIS MORNING I WAS 1kg HEAVIER. Wtf how does that make any sense at all.