Well, your thoughts were half correct...the nest-box should not have been added, as it only stimulates her hormones further. So as mentioned above, in the future, do not add a nest-box or any nesting materials at all, nothing that can be seen as nesting material.
Here's how to handle this situation: Now I would remove the nest-box right now and just put the eggs in the bottom of her cage, as the nest-box is making things much, much worse. She'll continue to lay on the eggs in the bottom of the cage. Let her lay on them until she figures out that they're not going to hatch, at which point she'll lose interest in them, and when she stops laying on them you can immediately throw them out. Remove anything that can be used as a nest or nesting material, and if she lays eggs in the future, just let them lay on the bottom of the cage, don't ever put a nest-box back in with her again, as that will just influence her to keep laying more eggs.
Is she on a Natural-Light Schedule? There are in-fact several different things that you can do that are non-medical to keep her from becoming so hormonal that she lays infertile eggs, and putting her on a Natural-Light Schedule is the very first thing you need to do, and keeping her on it strictly, regardless of the times of sunrise and sunset.
Also, if you haven't already, make sure you have both a Cuttlebone and a Mineral Block inside of her cage at all times, and buying a bag of Egg-Food to give her is also a good idea, at least until the eggs are gone and she's stopped laying. The number one cause of Egg-Binding in birds is low-Calcium levels, which cause the egg shells to be rubbery or even soft instead of hard, and they then get stuck in the cloaca. And Egg-Binding is 100% fatal without immediate medical intervention. So keeping lots and lots of Calcium with her at all times will help to prevent this, along with lots and lots of fresh veggies.