TSH with reflex means that TSH would be analyzed and if it were within the reference range, nothing else would be done. It TSH were outside the reference range, Free T4 would, then be analyzed. While reference ranges vary from lab to lab, most reference ranges for TSH are 0.45-4.50 or something like that. What's the range used by your lab? Your result of 5.09 should be outside the range used by most labs and should have triggered a Free T4 test...
Do you have any symptoms of hypothyroidism?