SOS! Bootcamp and bloating. 😭

Okayy y’all so I have days where I can look like a crack head because I’m so skinny looking and other days I look like I’m about to go into labor at any given time due to being bloated. Any suggestions? I leave for the military in 20 days and I need to get my weight down or at least prevent bloating. I’m enlisted in the navy and I weigh 162. Which is over my limit but my BMI saves me coming in at 27-30% ( I bloat like crazy) my BMI can’t be over 33%. Please help!