McDonald's Diet-week 1

Okay... ive been eating mcdonald's straight for like the past week.
Before i started on my mcdonalds diet, i was 5'8" and 154 lbs.
After a weeks diet of BigMac combo for lunch, and a 10 piece chicken mcnugget combo for dinner, this is how my body weighs in:
6'9" 144 lbs!!!!!!!
i made up that 6'9" part. i havent gained an inch actually.
but i didnt make up the 10 lbs weight loss.
i dont understand how im losing weight.
i dont exercise much.
i havent changed my active life in any way at all.
this revelation intrigues me and ill update as more more information piles in