Feeding in a separate container won't cause regurgitation. The small amount of handling it takes to move a snake from its feeding container back to its home simply isn't stressful enough. I frequently even rinse snakes under the faucet after feeding to clean them from bloody mice, vitamins, Nutribac, etc. and have never, ever had a regurge after moving a snake. I feed 80 snakes and move all but three of them for feeding.
I have, however, noticed a definite relationship to feeding while blue, before you can tell a snake is blue, when the snake is in the clear phase right before shedding and even, rarely, right after shedding, and regurgitation. I would call this somewhat common. I will not feed a blue snake, and try to avoid feeding when I suspect a snake may be blue but it is not apparent yet.
Other causes of regurgitation would be temps outside the preferred range, handling while the snake is digesting, a meal size too large, and more rarely, infection, parasites and disease.
Moving forward, do not feed your snake for 8-10 days following the regurge. This sounds drastic, but really it amounts to skipping one meal. Feed a prey item half the size of the meal that was regurged. If at all possible, obtain Nutribac and use that on all meals for a long period of time- months. Gradually increase the prey size back up to what the snake should be eating (prey 1 to 1.5 times the diameter of the snake at the snake's widest part). Take it easy; you don't want to cause a second regurge. Slit the back and sides of the mouse just through the skin with a small scissors to make it easier to digest. Do not handle for 48 to preferably 72 hours after feeding. Step up to the next prey size conservatively and gradually.
Do not feed your snake when it is blue, ever again. If you can't tell by looking, become observant so you can tell by behaviour. When the snake is hiding away in the evening, when it would usually be active, for several nights in a row, chances are it is blue. Young snakes shed about once a month, almost like clockwork. Keep a record of sheds and if the snake is due to shed and inactive, even if you can't visually detect the blue phase, you can bet the snake is blue. Just skip that meal. Sometimes you might even have to skip two meals. This will not harm your snake.