If I didn’t mail in my return , that means my return wasn’t filed right?

If you did not mail your return yet and plan to send it my mail vs. e-file then you should still file an extension today.

https://www.irs.gov/filing/free-file-everyone-can-file-an-extension-for-free

If you owe money, then you should make your payment here to avoid penalty:

https://www.irs.gov/payments

Right.  Unless you efiled it.   You can check your efile status here     

https://turbotax.intuit.com/tax-tools/efile-status-lookup/   

If you didn't efile, do you want to switch to efile?