Just because a sample is sent to a lab does not mean a GC/MS will be performed as the
primary analysis. An assay screen will still be performed first and if all 9 panels tested negative on the initial assay, the test is over there and then as a 'pass' - no confirmation GC/MS would be performed.
The GC/MS would only be performed on any of the 9 panels that have tested positive on the initial screen.

And if it goes direct to the lab, do you know if I'm being tested at 15 ng or 50 ng?
50 ng for the initial assay, 15 ng for the GC/MS.