When you amend your return the refund meter drops to zero and begins to calculate the difference between your original return and the information you have added.

If it shows a refund amount and:

• You received a refund on your original return, then this amount is additional and you will receive a payment for the additional amount.
  
• You owed taxes on the original return, this is the amount you over paid. The IRS will issue a payment to you.