African gray female how long an egg can stay in her womb

Question
I have a African gray female. She is holding her egg for last three weeks. She is happy all the time eating every thing. I tried oiling her for easy pass but no result so far.  I took her to a vet and she gave her antibiotics med after that she stop eating never passed the egg . When I stopped the med after two days she was normal eating again. I wonder how long an egg can stay in her womb. she is my baby,sleeps in my hand, spend most of the time with me on my shoulder and with me for last 3 years first year she laid 5 eggs last year she had only one now the first one is on the way for this year I had the doctor X-ray the egg and it  was upside down, may be that is a reason but vet helped to move the egg. It also occurred to me that it her feathers are becoming more dark than usual please help me to help her .I do have a male but she does not want him close. She fights when he even tries to come close. Any way you can help him so they can live happily ever after (My love has created this fuss I am guilty but the
way she show her love hard to ignore)

Answer
You need to either take her back to the vet or consult a different vet IMMEDIATELY!!!! She is egg bound and that egg could break any second and it could be fatal. You need to have her seen and they may need to do surgery to remove that egg. She needed to have that medication continued.

Get her to the vet! An AVIAN CERTIFIED VET!