I mean, only you know what's in your heart and what this means for what kind of person you are, your integrity, and if you are really doing the best you can for your own survival with work, as well as working towards medical school. Basically, how fair or justifiable it might be to do this. Sorta like someone who steals bread when they are starving. But was this unavoidable? Is this the only way to cope with the problem? What will you do in the future not to repeat this offence?
I mean, some people have lied for medical insurance or food stamps, because they truly needed those things and working more than they already were would not solve those problems for them.
The main issue as I see it, is it doesn't sound like you are in the "perfect storm" of things.
The big issue, is that you're on a slippery slope. You have to use good judgement for when you're going to break rules, rules that could have big consequences, acts that are not entirely ethical even if there might be some sort of ethical argument for (like the example I gave). As someone noted, you have to answer to yourself, you are the only person to know when and why you do these things, unless you're caught. That judgement is what determines if you are in fact caught, like if you do this too much too often too stupidly. That judgement is the only thing protecting you from harm, ultimately. What does this say about your judgement?
Getting into a pattern or starting to think this is going to be a way for you to deal with balancing things to meet requirements, when the road just gets harder, is only going to bite you one day. It's Russian roulette. So sure, you've pulled the trigger a few times. But the more you pull that trigger, the more likely it is one day that you catch a bullet.
When you break the rules, when you feel like you have to do what's wrong, when you are taking a chance like this, the big thing to ask yourself before doing something like this, is are you going to be able to never do this again? If you can't say that and keep to that, then best not do it now. If you do allow yourself to do this, I really hope that it hurts your soul a little and that this will mark the beginning of a lesson learned and a change in behaviour, a promise to yourself not to do this again, a promise that isn't empty, that you will be able to keep.
I guess in my mind, I'm only able to absolve myself for lapses when they are in fact lapses. That means making sacrifices in the future not to do it again. To do my best so this sort of thing is rare, and that I've honestly done all I can to avoid it in the future. What will you do for this to be the last time you ever do this?
I'm not going to judge you for what you've done or what you plan to do. But, you are not doing yourself any favours. I hope that you can do better in the future, for your own sake.
ETA: And yes, if this is ever found out or you do anything similar in the future and are caught, your career could be over before it starts. This is true for SO many things. You need to be as upstanding as you can be, in every way. So many reasons for that to be true. Everything you do that is breaking rules can ultimately destroy a career in medicine. Dishonesty above all. You can be forgiven SO many things that could otherwise destroy you, despite what I just said, if you are honest.
The hope for any future physician, is that you carry a sincere desire for honesty, integrity, responsibility. And everyone on the road to being a physician makes mistakes and does things they are not proud of. Yes, really. No one is perfect. However, you need a strong moral compass for so many reasons, not the least of which is for patients, but also yourself. Don't you want to do your best so that you never have to lie if you did so? So you never have to put everything you've ever worked for on the line? So that you can feel proud of your conduct, so that others can trust you with their lives? Imposter syndrome is real, and it hurts, it happens to and hurts even people that are a step above psychopath and even have tendencies towards being laissez faire.
This has to stop happening in your life.