Why did I receive a refund of taxes that I paid?

They sent you a refund?  Did you enter any 1099R?  If 1040 line 4a is a lot less than 4b (which should be ok) the IRS has been lowering the taxable amount on 4b and refunding you.  But then they will eventually want it back.

Did you make estimated payments and forget to enter them?
If you made estimated payments see if they are on line 17.  Sometimes they end up line 16 with witholding.  If that is the case the IRS will eventually see line 16 is wrong and ask for it back.

Unfortunately none of the scenarios you describe apply to me. I’m concerned that turbo tax miscalculated my taxes owed. Is that possible?

sure it is.  but most likely you enter some number incorrectly or not at all that substantially and falsely increased your tax liability.   in 2 to 3 weeks you should get a notice from the IRS explaining the changes.  then you can determined who messed up.