Amoxicillin would have to be ordered online.
I really don't know about the Erythromycin, it's not something I see recommended at all - I'm not sure for the reason. @Eggcessive or @casportpony may be able to tell you more about this particular antibiotic.
If she were mine, I would source...
Anytime you get something yucky like that, if you can get photos...(I know that sound so strange, but it's the ER thread after all LOL)
It's good that you are able to keep working on it. I'm rooting for the both of you :fl
If your vet can get meds for you that will great. Amoxicillin dose is...
Poor girl!
You are doing what you can for her, hopefully she will hang in there with you and you can get it all out.
I would worry about development of infection, so if possible giving her an antibiotic would be good. I would use Amoxicillin, it can be ordered online...
I would continue making water available.
Hard to know if she's constipated/blocked with poop, there's a soft shell egg in there or what.
Sounds like she's trying to expel something.
I think I would give the Calcium as suggested by @azygous Giving her coconut oil won't hurt anything either.
Is she pooping at all? What's that like?
Drinking lots of water usually indicates crop issues. I would make water available, but withhold food and see what the crop is like in the morning.
Read this article and let us know how she's doing...