At that concentration, temperatures are in the many trillions of degrees, which is too hot for even quarks. Thus only energy was in the regime, as is supposed. With expansion, temperatures dropped accordingly and quarks formed, then nuclei, etc.
But the best objective evidence we have (from CERN) only allows the testing of any BB model to about the time after the first trillionth of a second. Planck, long ago, found that the smallest unit of time is 1E-43 (10^-43) sec., hence you'll see this in publications.