I had a young hen this year. Actually I thought she was too young to lay yet. She was just 4.5 months old. Like yours she was sitting there and you could just see something was not right. I got worried. I seperated her and she was sitting there pressing like crazy at times. The only thing I could think of was to take some vegetable oil and a syringe and put about 10 or 15ml in her cloaka. The next morning she had layed a little egg. She has been fine ever since. If you feel like she is having a hard time you might try that to see if it helps her.Thank you I get worried that she is in pain ! But then she will be completely fine the next day and then she will either lay a regular egg that is small or the next day it’s very big