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When you say you messed up at 18 (and a lot of us have been there so don't stress about it now), did that mess up include Discover? It is unusual, but not unheard of, to be declined for a secured card.
Did you try Capital One or Credit One? Both are pretty easy (though the limit will be low).
If they took out the deposit, and then decline you, they'd have to refund the deposit (probably via check), and I can't imagine a bank the size of Citi having a wasteful/dumb process like that, so you are probably fine. I would guess they are just verifying the funds/setting up your account.
Post back when you hear back. You could always call them as well, but a CSR may not know.
Same thing happened on mine. It seems to be pretty standard on their secured card. If the deposit came out I would say you are good to go.
Same thing happened with me.
They took the deposit - you're probably good to go!