Was it a fully formed egg just minus the shell? Just a yolk? Any membrane at all?
I personally would supplement her calcium ASAP (starting today), for several days- a week.
Even tums will do in a pinch,
But 1/2 caltrate +D3 is better (although 10x more expensive).
If she was just starting to lay I wouldn’t be alarmed, but at 3 years of age it could be a reproductive problem such as your other one had. internal laying, salpingitis, etc .
You may want to do an internal exam (with glove and lubrication) to see if anything was left behind in there.