I'm young (25) and still look and feel droopy, though I credit breastfeeding three babies in four years to that particular feature of my breasts and belly
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Foundational garments are a must! Also, carry yourself with confidence and feel good in your skin - own it! That inner expression of your feelings (I feel good, I look good) can mask a whole boatload of figure ills. So much of 'the way I look' is a mental game. I've seen mediocre-average-looks obese women who appear, to me, absolutely stunning, because of how they carry themselves and relate to the world. In the same way, stunning model-esque skinny Minnies who are almost mouselike until a second or third glance is spared, because they just curl in on themselves and their insecurity is palpable.
Short of the aforementioned foundation garments, plastic surgery, or a truly intensive body-shaping with heavy weights, drooping is genetics and age and life events (weight gain, hormones, injuries, etc). It may be a real, physical thing we cannot easily change. But a fair portion of it is energy and attitude, and those are entirely within your control.
Experiment with your self-talk when you walk around - when others look at you, what do you think or feel? Try different supplements, even sleep and waking times - these can hugely affect your energy and mood. Maybe even mess with your macronutrients - more fat, less grain. That can afford you energy and vitality in spades, if you're prone to inflammation from starch and sugar as I am.
You control so much more of your perkiness and energy than it first seems, and age- or weight-related drooping aside, what you project to the world and how you feel about yourself is sending the far more vital message.