EYP

My chicken annie had became very ill. I noticed her stance/gait was similar to a chicken that is egg bound and abdomen was huge so i started treated immediately because i wasnt sure how long she waslike that. I know a chicken that is egg bound has about 48 hours to get the egg out or death. I gave her Epsom salt bath. calcium in our food mineral oil around in her vent and nothing seems to work.I was too scared to manually extract the egg as I weighed my pros and cons of doing so. So I continued the Epson salt bath and calcium on top of her food and still no eggs 72 hours later. I then came acrossed eyp and that seemed to be what fit her symptoms the most I had a chicken with EYP and was prescribed antibiotics and metacam. since this was awhile ago I was unsure how long I should treat. can someone help me out and let me know how long they treated their chicken with a eyp? I started antibiotics and metacam 6 days ago. the swelling that was in her abdomen was the size of a melon but now is the size of a grapefruit or orange she is walking normal now and doesn't seem painful but I don't want to stop treatment too soon should I continue until the swelling is gone? Will the swelling ever go down with eyp? could it be something else that causes swelling in the abdomen that goes away with antibiotic treatment? she is 9 years old and she's just been the best chicken any answers are very appreciated thank you