You did the proper thing when you found her in obvious distress. You possibly headed off a much worse scenario.
I have a hen like yours. Spring before this last one, she got herself into trouble laying two eggs consistently per cycle. It didn't take long for one to get stuck inside since there isn't enough calcium usually in the shell gland for two eggs at a whack.
I had her on daily calcium citrate + D3 for a month before she started to produce one normal egg per cycle. Since then, a good seventeen months, she's been producing one normal egg per cycle, and she lays regularly. (She's an EE) But almost all her eggs have calcium "pimples". I haven't needed to give her calcium except for once or twice when she would spend way too long in a nest. Once she produced a normal egg, the calcium was stopped.
These hens of ours need careful watching. There is obviously something out of whack in their reproductive systems that include poor calcium absorption and a tendency to have laying issues. Just keep the calcium supplement handy and pop a pill into her if you suspect her beginning to have a problem.
Keep up daily calcium until the eggs appear normal, then stop. Only resume again if she appears to start having problems.