What it call to lose weight and gain it back again

Hmm I don't know in what way you're referring to, but something called yo-yo dieting or the yo-yo effect might be what you're looking for. It's when someone looses weight and then regains it back.

Hoping I helped!

I would call it fluctuating Weight since your weight never stays the exact same

10/10 recommend bring pads/tampons with you no matter what. im 16 & i’ve had mine since i was 12 and they’re still it regular, but id suggest using the glow app, many women use it for fertility reasons but i use mine specifically for the period tracking portion and it guesses when your next period will most likely be for the next two months. i dont believe theres any way to delay your period, so id say hope for the best but make sure to bring all of your stuff just incase. have a good cruise!