I think she's gone... it's much too late to try to save her since she's an autoflower... It sounds to me like you didn't give her any water in the first 10 days of her life? I could be misinterpreting what you've said... But you need to keep the soil moist (not soaking) around a seedling, whether its shell is on or not... but now, since she's about 2.5 weeks old, there's no time for her to catch up to her inbred schedule and I'm afraid you're going to have to start over again.
Good luck....