unexplained blood glucose levels

I play golf regularly, and afterwards I have two pints of fresh orange and soda mix. Prior to going on a DAFNE course I was quite cavalier, in then getting in the car and driving home.
Now I check my blood glucose level when I finished golf. This was about 4.1, so by pure coincidence the drinks were moving me into a safe level to drive.
When I returned home I checked my BG level prior a snack and it was 10.6. I have never registered that high a level before, so I scrubbed my hands again, and retested with the same result.
This reading was 7 hours after breakfast and both QA and BI injections.
I decided not to eat, and wait until my evening meal to retest and apply any correction.
3 hours later, prior to eating, I checked my BG and it was 5.3.
I would not have thought that the Background insulin could dissipate over 5 units of BG in 3 hours.
I could have assumed that excess glucose is absorbed by the liver, but my experience of the DAFNE course is that most of my assumptions tend to be misguided.
I am looking for some explanation as to where all this glucose has disappeared to, on the basis that if I understand the mechanics, I can manage the situation properly