Coop Crazy - the pushing she is doing when you stick your finger up her vent is a normal reaction - I dare say most of us would do the same under those conditions!
This can work in your favor - you need to put your finger up in her vent far enough that she can not push it out. I don't know how to tell you how far is far enough - this is what I do. I put about half of my finger in the vent. Don't remove your finger when she pushes. The pushing may drop the egg down enough for you to feel it. If it is a soft shelled egg, you can break the shell and then kind of move your finger in a slight digging type motion to try and bring a part of the soft shell down enough that you can work it out far enough to get ahold of it and gently tug it out of her - pulling it gently with each of her pushes.
If it is a hard egg shell, I'm afraid I don't have much advice. I've had to remove several soft shells, but never a hard shell. Hopefully someone that has dealt with that will weigh in.
Best of luck! Please let us know how it goes.
Penny