If you already filed your tax return there is no way to cancel it. You have to wait until the IRS either accepts it or rejects it. If the IRS rejects it you can make the corrections and resubmit the tax return. If the IRS accepts the tax return you will have to wait until they process it and pay your refund, then file an amended return to make the corrections.
The IRS will start accepting or rejecting tax returns on January 26.