Sounds like she could have sour or impacted crop, or possibly an impacted gizzard. Check her crop in the morning, at which time it should be relatively empty and flat. If it isn't, and it feels hard, then she probably has impacted crop. If the crop is balloon like and squishy, and there is a sour smell coming from her mouth, I would suspect sour crop.
To treat impacted crop, give her some olive oil and gently massage the crop. In many cases, this will dissolve the obstructing mass and the bird will be fine. Don't let her eat any more hard stuff, like grain or grass, either. If the massaging and limiting of hard food doesn't clear the crop, you may have to perform crop surgery if you want her to live.
I'm not sure on the treatment for sour crop, as I've never really dealt with a severe case of it. When one of my birds had a mild case, though, simply putting probiotics in her water and keeping her clean/comfortable cured the problem within a few days.
