My return was accepted on Feb. 11. Tax owed and paid on April 15 via direct debit. However I received refund check in the mail on April 30. Should I be suspicious.

I used TurboTax to fill out return, and submit for payment.  Taxes were due from me to IRS.   Return status on Feb. 11 2018 was 'accepted'.   Tax payment from me to IRS processed via bank account debit on April 15.   On April 30 I received a small refund in US mail.  Should I be suspicious of identity theft