Yes, there is no need to use so much calcium any way, as they get plenty of everything they need from their rodent prey.
I would not just assume it is crypto right off the bat either, as it is MOST likely from too large a meal that it could not properly digest. DO NOT attempt to feed it more meals until it has been looked at, I strongly suspect it has some nasty intestinal bacteria from the putrid previous meals. I would imagine a two-dose regimen of Flagyl(metronidazole) could EASILY be all that is needed here. This will kill the bad protazoa/pathogens as WELL as the GOOD bacteria that is needed for proper digestion, so STOP offering it any food until the snake has been looked at and helped. Feeding at this point will only lead to more regurges and a DEFINITE downward spiral that could easily end up killing it. Offering food at this point is the WORST thing you could do right now until you takle the intestinal problem.
Hopefully the vet will know the proper course of action, but MANY vets don't know diddly squat about reptile medicine whatsoever. The snake should get a dose of of Flagyl at the rate of 50 mg./per kg. of body weight given orally, and another follow-up dose 10 to 14 days later. NO FOOD should be offered until a good week or so AFTER the last dose so the snake can replenish it's vital acids, electrolytes, enzymes and gut flora before being fed again. And when it IS FED again, they should be very small meals for a while to make certain they stay down and are digested properly.
After several very small meals, you could GRADUALLY increase the size back to normal, just make sure you never offer these gigantic meals again, that is of no benefit at all, and usually only makes it tough on the snake's system as you have already found out.
Sometimes snakes develop this from fouled water too, so who knows, but I would bet a dollar to a donut some Flagyl at the proper dosing will take care of this. Flagyl is very reptile friendly too!
good luck!
~Doug
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"a snake in the grass is a GOOD thing" 
my website -serpentinespecialties.webs.com