How long ago did you mail your amended return? You cannot e-file a 1040X. It must be printed, signed and mailed to the IRS.
After you print, sign and mail your amended return—1040X— to the IRS wait about 3 weeks and then you can begin checking on it at the IRS website. Be aware that it can take at least 3-4 months for an amended return to be fully processed (or sometimes even longer.)