Yes, you must have done something wrong, but we have no way of knowing what you did. Below is a link to the instructions for amending a return. But you have to first undo whatever changes you made so that you start the amendment process with your return exactly as it was when you originally filed it.
How do I amend my federal tax return for this year?
If you have not already done so, before you start to amend save a PDF of your original return. In TurboTax Online you will not be able to access the original once you start to amend.