Is her crop emptying?
I would work on hydration and get the extra calcium into her. If she's not drinking on her own, then you'll want to syringe or tube fluids into her.
Since she seems to be in distress, I would not soak her, it may send her over the edge.
I'd work on hydration and getting the calcium into her. For Tums, try to break it into a couple of pieces, then pop a piece into her beak and let her swallow, repeat. She may shoot the piece back out, but...