Thank you @xmasbaby0 for your reply! Like I mentioned in the original post, the IRS has already accepted my return. When you look up instructions from TurboTax on how to amend your return, it says you have to wait until it's been accepted by the IRS, which it has. But the next step in TurboTax's instructions seem to indicate that there's an "Amend" button, which there isn't. Very disheartening to hear that it takes 2-4 months for an amended return to be processed, but I guess I only have myself to blame. : (
