sorry didn't mean to suggest it was your fault
your GP is right, logistically getting the samples from a collection center to the lab is a nightmare, when the clock is ticking. and this can cause slow swimmers. it is my understanding its not the FS that does the testing but the lab, so when you find your FS he may suggest a repeat SA to rule this out.
it takes a massive effort to get the sample collected, big shame if the courier gets stuck in peak hour traffic, or something equally silly. sulli and nic's are a good lab (i worked for then when i lived in bris vagas ) and they make every effort to do the right thing.

hope you get some answers. its sooo0 stressfull this TTC. i don't know if its physiological or biological but once you decide you want to be UTD, you want it NOW
my DH and i have been trying for #3 for more than a year, with an along the way.
best of luck