Go back and check your bank records. Was the tax due actually paid out of your bank? Did you mail them a check or did they automatically debit your Account? If they pulled it out of your account then they had to process the actual return. That should be enough proof they got it or how else could they take the payment?
When you log into your account you should also see the status and if it was Accepted or Rejected, Started, Printed, Ready to Mail, etc. what does it say?
And check your emails. When you efile you get back 2 emails. The first email only confirms the transmission. The second email says if the IRS (or state) Accepted or Rejected your efile.
