First, just wait. (I can't stress this enough.) Once your originally submitted and accepted return is processed and your refund is issued, then you'll "know" what to do.
There's a fair chance the IRS will catch the error, correct your return on their end and then issue the appropriate tax refund or bill you for any amount due. Basically, you will get a form letter in the mail from the IRS. The letter will have a form number in the top left or right corner that begins with "CP" or "LTR".
If the IRS issues your refund as originally filed with no corrections by them (could happen, but I doubt it) then you'll amend your tax return to correct it and file that amended return with the IRS. You'll also have to pay the IRS any excess they may have refunded to you.
If the IRS does catch the error and corrects it on your behalf, then you'll amend your return *WITHOUT* submitting the amended return to the IRS, just for the sole purpose of insuring what gets imported into next year's return is correct. Depending on a number of factors, this may or may not be necessary.
