So yes and no. Some of this depends on what sort of “loop” you’re stuck in, which I can’t answer unless I have more details. The rest doesn’t depend as much on that.
On one hand, 21 is extremely young—which means you have an absurd amount of wiggle room and time to course correct, even if you’ve done some really dumb stuff.
On the other hand, time only starts to move faster and if you don’t commit to course correct at some point you’ll end up a lot older in a way tougher spot.
I think the answer here is some sort of average of extremes (like it is for most things in life). You shouldn’t worry about the future too much because you’re so young, but you should start taking action to course correct now so that the next 5-10 years are easier.
Yeah, my understanding of the physiology is that taking it that early leads to rebound sleepiness in 4-6 hours after waking. I think it definitely does, but the immediate caffeine helps if you have a job that demands immediate alertness lol.