Confused, but should I be concerned?

I recently had a routine fasting blood test, which showed fasting blood glucose of 5.3 mmol. This obviously isn't even a prediabetic reading and no one seemed at all concerned, but it seemed to me to be edging close to prediabetic levels, so I took a couple of additional steps that have yielded somewhat conflicting results:

• I used an Accu-Chek Performa BG monitor to test my BG at various times. I measured a couple of FBGs first thing in the morning (one was 5.7, the other 6.1), and I've taken several postprandial measurements 2 hours after eating, all of which have fallen between 4.4 and 5.5 (even after large, carb-heavy meals).
• I had an HBA1C test done, which returned a strikingly low 4.4%

Something about this combination of results doesn't quite add up for me (i.e. the FBGs seem disproportionately high relative to everything else), so I'd be interested to get your views on whether you think I should (a) be at all concerned and take any further steps or (b) stop being ridiculous and forget about this altogether.

Further context:

• I am 32, have a BMI of 20 and no family history of diabetes, do moderate exercise 2-3 times per week and have a diet that is OK from a caloric perspective but full of sugary treats.
• The only 'symptom' I have that would arouse any suspicion is feeling very tired after eating a large, carb-heavy dinner (more than I used to), although I recognise this might be a pretty normal response.

Thanks in advance for your input!
DM