The way to check this would be to have an IgG IgM blood test done before and after a covid swab test; be sure the covid test is done with short swabs, as in the traditional flu a/b strep test.
Example:
I had a blood test and it showed no IgG IgM antibodies, then I got a covid swab test, which was negative.
Next step would be for me to go back and get a IgG IgM antibody blood test, and see if it shows any antibodies.
Or, in addition to the IgG IgM test, get a T-Cell test.
I’ve been wanting to get that one anyway.
The IgG IgM tests are $25 at Kroger’s pharmacy.