She may also has some type of fungal infection going on in there. I had something similar but without the comb being swollen. The crop was huge but felt like it was full of fluid, air, or gasses, or maybe a combination of all. I treated for a fungal infection and fed only a handful of crumbles twice each day. I was also administering epsom salt water with a syringe to help get things moving. Within 2-3 days, the crop started to empty and I slowly gave her more food each day. Things look back to normal now. Good luck to you, hope you can figure this one out.
