Can i borrow some calories?

Yes. You can also 'save' calories throughout the week and have more on the weekend, so long as your overall calories meet your weekly target.

For example, suppose your daily calorie target is 1600. If you have 1500 Monday through Saturday, you can have 2200 (1600 + 600) on Sunday.

Fifty isn't a big deal either way. With that small a number, it's no big deal if you ignore it: Likely you'll be a little over some days, a little over on others.

If you have MFP set up to lose 0.25 pounds a week (which would be the slowest normal rate), it's given you a 250 calorie deficit. If set up for faster loss, it's a bigger deficit than that. An extra 50 calories eaten leaves most of that deficit still happening . . . and besides, 50 calories is in the realm of probable errors in our other estimates (scales are imprecise by a tiny bit, one apple sweeter than the next, etc.).

That isn't an excuse to start going over goal every single day, but it's a way to recognize that close is good enough, the majority of the time, and it's not necessary to stress about it. I'm betting you're under by a few calories some days, too.

Personally, while losing weight, I found that "borrowing" calories from the future (in meaningful numbers, i.e., > 50) was not a great idea. It was fine for me to "bank" a few calories ahead of time to eat a bit extra on a future special occasion (like eating maybe 100 calories less than goal for a week to "save up" extra for a dinner out on the weekend, as long as my overall weight loss wasn't extremely fast.

In contrast, "making up for it" after the fact was more likely to lead to hunger and maybe unplanned over-eating at some future point, potentially getting me into a cycle of undereating to "make up", then overeating out of relative deprivation. Not useful, for me. I was much better, if I had an unpredicted over-goal day, just to let it go, and get back on my normal track afterward right away. This may not be true for everyone, but it was what worked best for me.

If one does the math, the calorie overage (above maintenance calories) usually amounts to a few hours delay in reaching goal weight, usually at most a couple of days. As long as it isn't frequent, that really just doesn't matter.

I think it's good to be disciplined (and not sloppy) about calorie goals. But, psychologically speaking, I think it's also important to keep things in perspective, not stress over relatively minor/rare things, etc. It's possible for this process to become obsessive or anxiety producing - some of us are more vulnerable to that than others - so I think it's helpful to be a bit chill about stuff that's a drop in the ocean, in terms of big picture.

What we do on the majority of days determines the majority of our progress.

Best wishes!

You can, but it could be a slippery slope for some people triggering anxiety or some unhealthy dieting behaviors. being a little over or a little under is fine. As long as you more or less eat within the range of your chosen deficit most days you'll lose weight at a close enough pace. You don't have to hit calories perfectly every day, and it's okay to have days around maintenance calories every now and then (or even over maintenance sometimes if it doesn't happen often.)

The harder you make things for yourself the harder it will be to stay the course.

I would really urge against this.. correction is a slippery slope to disordered eating.. especially when the numbers over can sometimes be bigger..

If you go over the best thing you can do is wake up tomorrow and carry on.