Have you actually e-filed your return? Did you hit the Transmit/Submit button? (or Did you Print and Mail your return?)
If so, You need to WAIT until you find out if your return has been REJECTED or ACCEPTED.
Then it is BEST if you wait until you actually receive the refund (or payment due is taken from your account) based on your already filed return; then you can start the amendment process
If it has been rejected then you can simply make the corrections required to fix the rejection AND at the same time add the new information, and re-submit your CORRECTED e-filed return.
If it has been accepted you will have to prepare and mail an amended return ---BUT WAIT until you receive your refund before filing the amended return.
A Form 1040-X amended return MUST be PRINTED and MAILED; and usually takes 3-4 months to be processed.
Perhaps some terminology/definitions would be in order:
AMEND:- your return is what you do AFTER your return has been filed and accepted by the IRS and/or state. (No additional charge)
CHANGE:- your return is what you do BEFORE your return has been filed --simply go back to the respective information and change it as needed.
CORRECT:- your return is what you do AFTER you attempted to file your return and it is rejected by either IRS, or state --again, simply go back to the respective information and change it as needed.
Above all DO NOT DO ANYTHING until you find out if your return is rejected or accepted.
When mailing a printed return it is always a good idea to go to the Post Office and mail it 'Certified' with 'Return Receipt'. That way you will have proof that they received it and when it was received.
My dilemma is whether to file State (which I have not yet mailed) with the known errors in the Fed, or to file State with Fed that contains corrections. I agree: I must wait for Fed outcome to do Fed correction. How should I handle State before April 15 deadline?