How did I lose 5 pounds in 3 days?

That and you could be dehydrated. That will make you drop a few pounds.

Dehydration will do that, and if you are eating less and/or eating lots of soups, stews, and “lighter fare”, there will be less… hmm… lingering in your digestive tract. It all adds up.

So 1–2 lbs less of water per day, and 1–2lbs of less of “in transit” fecal matter over 3 days, and that could account for your loss. If you’ve been VERY sick and eating nothing, you could hypothetically lose 0.5–1 lb of tissue from starvation around the 3 day mark, MAYBE. But in the first couple days, it’s just water and waste loss since your body would have to deplete the glucose (glycogen? damn, biology class was a long time ago) in your bloodstream and ..liver?... first before attacking the muscle tissue and fat storage for catabolic weight loss.

your alien sponsor has left you? lol, sorry, being silly

I lost a bunch of weight when I had the stomach flu… for reasons you probably don’t want to imagine