Drinking will make you gain weight temporarily, yeah. Alcohol dehydrates you and adding carbonated, caffeinated beverages on top of that makes it worse.
Next time, make sure you drink water with or between your alcoholic drinks. Also be sure to drink a full glass of water before you go to bed - it will help with the retention and also with the hangover symptoms the next day.
Go take your walk to the store. Get veggies and fruit and binge on that if you must binge!
Drink more water, and avoid anything salty.
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